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15390..15419 , 15420..15449 , 15450..15479 , 15480..15509 , 15510..15539 , 15540..15569 , 15570..15599 , 15600..15629, >>NextTravel_Word_Problems/564822: Sarah takes 40 minutes to walk to her office and only 12 min if she rides her bike. Her speed when walking is 7 miles per hour less than her speed when riding her bike. (assume she takes the same path to her office). What is the distance to her office. 1 solutions
Answer 365709 by ankor@dixie-net.com(15622) on 2012-01-30 21:20:13 (Show Source):
You can put this solution on YOUR website!Sarah takes 40 minutes to walk to her office and only 12 min if she rides her bike.
Her speed when walking is 7 miles per hour less than her speed when riding her bike. (assume she takes the same path to her office).
What is the distance to her office.
:
Let s = his walking speed
then
(s+7) = his biking speed
:
Write a distance equation; dist = speed * time
We need the time in hrs
:
 s =  (s+7)
Reduce the fractions
 s =  (s+7)
Multiply by 15 to clear the denominators
5(2s) = 3(s+7)
10s = 3s + 21
10s - 3s = 21
7s = 21
s = 21/7
s = 3 mph is his walking speed
:
Find the distance
 (3) = 2 miles
Check the distance
 (3+7) = 2 miles also
|
Age_Word_Problems/564797: Last year,tom was thrice as old as his sister.next year,he will be twice as old as his sister.what will be tom's age when his sister is 12 years old? 1 solutions
Answer 365632 by ankor@dixie-net.com(15622) on 2012-01-30 19:08:00 (Show Source):
You can put this solution on YOUR website!Let t = Tom's present age
Let s = Sister's present age
:
Last year,tom was thrice as old as his sister.
t-1 = 3(s-1)
t-1 = 3s - 3
t = 3s - 3 + 1
t = 3s - 2
:
next year,he will be twice as old as his sister.
t + 1 = 2(s+1)
t + 1 = 2s + 2
t = 2s + 2 - 1
t = 2s + 1
replace t with (3s-2)
3s - 2 = 2s + 1
3s - 2s = 1 + 2
s = 3 yrs is sisters age
then
t = 3(3) - 2
t = 7 yrs is Tom's age
:
what will be tom's age when his sister is 12 years old?
Sister will be 12 in 9 years
therefore
7 + 9 = 16 yrs will be Tom's age
|
Linear-systems/565025: I have no clue how to solve Systems of Equations!!!??? HELP EX: y=3x+6
y=x+2
Any Suggetions?? 1 solutions
Answer 365597 by ankor@dixie-net.com(15622) on 2012-01-30 18:25:04 (Show Source):
You can put this solution on YOUR website!y = 3x + 6
y = x + 2
this one is easy to solve using substitution
we know that y = y, therefore we can write it:
3x + 6 = x + 2
3x - x = 2 - 6
2x = -4
x = -4/2
x = -2
:
Find y
y = 3x + 6
replace x with 2
y = 3(-2) + 6
y = -6 + 6
y = 0
:
Check solutions in the 2nd equation
y = x + 2
Replace x and y and see if it is equal
0 = -2 + 2
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Equations/564750: The difference between the two numbers is equal to the double of the smaller number. If the quotient dividing one by the other is 3, find the numbers. 1 solutions
Answer 365588 by ankor@dixie-net.com(15622) on 2012-01-30 17:55:08 (Show Source):
You can put this solution on YOUR website!Two numbers, a & B
:
"The difference between the two numbers is equal to the double of the smaller number."
a - b = 2b
a = 2b + b
a = 3b
:
"If the quotient dividing one by the other is 3,"
 = 3
:
find the numbers.
Replace a with 3b
 = 3
:
All we can say about this a = 3 times b, Any numbers with this relationship will work
|
Money_Word_Problems/564881: Equal amounts are invested at 6%, 7%, and 9% annual interest. If the three investments yield a total of $814 annual interest, find the total investment.
1 solutions
Answer 365565 by ankor@dixie-net.com(15622) on 2012-01-30 16:53:51 (Show Source):
You can put this solution on YOUR website!Equal amounts are invested at 6%, 7%, and 9% annual interest.
If the three investments yield a total of $814 annual interest, find the total investment.
:
Let x = amt invested at each interest
;
.06x + .07x + .09x = 814
.22x = 814
x = 
x = $3700 invested at each
therefore
3(3700) = $11,100 is the total
|
Inequalities/564837: Please help me with this:
Solve using the addition and multiplication principles.
34>4-6x 1 solutions
Answer 365558 by ankor@dixie-net.com(15622) on 2012-01-30 16:37:14 (Show Source):
You can put this solution on YOUR website!34 > 4 - 6x
Add 6x to both sides
6x + 34 > 4
Subtract 34 from both sides
6x > 4 - 34
6x > -30
divide both sides by 6
x > 
x > -5
:
Check solution x > -5, let's say x = -4
34 > 4 - 6(-4)
34 > 4 + 24
34 > 28; which is true
:
However if you try it with x = -6, it will not be true as you would expect
|
Exponents/564981: I am trying to solve this Problem. Please help. thank you.
The flow of water F in cubic feet per second over a wier, a small overflow dam, can be represented by F=1.26H2/3, where H is the height of the water in meters above the crest of the wier. Find the height of the water if the flow of the water is 10.08 cubic feet per second. 1 solutions
Answer 365554 by ankor@dixie-net.com(15622) on 2012-01-30 16:25:59 (Show Source):
You can put this solution on YOUR website!The flow of water F in cubic feet per second over a wier, a small overflow dam, can be represented by F=1.26H2/3, where H is the height of the water in meters above the crest of the wier.
Find the height of the water if the flow of the water is 10.08 cubic feet per
second
:
1.26H*  = 10.8
multiply both sides by 3
1.26H(2) = 10.8*3
2.52H = 32.4
H = 
H = 12.857 ~ 13 meters
|
Mixture_Word_Problems/564693: a mixture of acid and water is 35% acid. if the mixture contains a total of 50 liters, how many liters of pure acid are in the mixture? how many liters of pure water are in the mixture? 1 solutions
Answer 365549 by ankor@dixie-net.com(15622) on 2012-01-30 16:10:19 (Show Source):
You can put this solution on YOUR website!a mixture of acid and water is 35% acid.
if the mixture contains a total of 50 liters, how many liters of pure acid are in the mixture?
:
.35*50 = 17.5 liters of acid
:
how many liters of pure water are in the mixture?
:
50 - 17.5 = 32.5 liters of water
|
Travel_Word_Problems/564711: you drive to the beach at a rate of 120 kilometers per hour. On the return trip you drive at a rate of 60 kilometers per hour. What is your average speed for the entire trip? 1 solutions
Answer 365542 by ankor@dixie-net.com(15622) on 2012-01-30 15:56:40 (Show Source):
You can put this solution on YOUR website!you drive to the beach at a rate of 120 kilometers per hour.
On the return trip you drive at a rate of 60 kilometers per hour.
What is your average speed for the entire trip?
:
Let a = the average speed for the whole trip
let d = the one-way distance of the trip
:
Write time equation, time = dist/speed
:
To time + return time = total time
 +  = 
Multiply by 120a
120a*  + 120a*  = 120a* 
cancel the denominators
ad + 2ad = 120(2d)
3ad = 240d
Divide both sides by d
3a = 240
a = 240/3
a = 80 km/hr is the av speed for the round trip
|
Geometry_Word_Problems/564823: the measure of one of the angles of a triangle is 35. The sum of the measures of the other two angles is 145 and the difference between their measures is 15. What are the measures of the unknown angles? 1 solutions
Answer 365538 by ankor@dixie-net.com(15622) on 2012-01-30 15:46:34 (Show Source):
You can put this solution on YOUR website!the measure of one of the angles of a triangle is 35.
The sum of the measures of the other two angles is 145 and the difference between their measures is 15.
What are the measures of the unknown angles?
:
Three angles, A, B, C
:
A = 35
B + C = 145
B - C = 15
------------adding eliminates c, find B
2B = 160
B = 160/2
B = 80 degrees
Find C
B + C = 145
80 + C = 145
C = 145 - 80
B = 65 degrees
;
:
Check this; 35 + 80 + 65 = 180; which is what every triangle should have
|
Travel_Word_Problems/564682: A boat in distress, 21 nautical miles from a marina, travels toward the
marina at 3 knots (nautical miles per hour). A coast guard cruiser leaves
the marina and travels toward the boat at 25 knots. How long will it take
for the boats to reach each other? 1 solutions
Answer 365531 by ankor@dixie-net.com(15622) on 2012-01-30 15:32:30 (Show Source):
You can put this solution on YOUR website!A boat in distress, 21 nautical miles from a marina, travels toward the
marina at 3 knots (nautical miles per hour). A coast guard cruiser leaves
the marina and travels toward the boat at 25 knots. How long will it take
for the boats to reach each other?
:
Since they are going toward each other the relative speed is; 3 + 25 = 28 knots
hence; (dist/speed = time)
 =  hr which is 45 minutes
|
Travel_Word_Problems/564882: Tanner Jones and Sheldon Furst received walkie-talkies for Christmas. If they leave from the same point at the same time, Tanner walking north at 2.5 mph and Sheldon walking east at 3 mph, how long will they be able to talk to each other if the range of the walkie-talkies is 4 miles? 1 solutions
Answer 365523 by ankor@dixie-net.com(15622) on 2012-01-30 14:29:56 (Show Source):
You can put this solution on YOUR website!Tanner Jones and Sheldon Furst received walkie-talkies for Christmas.
If they leave from the same point at the same time, Tanner walking north at 2.5 mph and Sheldon walking east at 3 mph, how long will they be able to talk to each other if the range of the walkie-talkies is 4 miles?
:
Let t = walking time of the two boys to reach max range
:
2.5t = dist walked by T
3t = dist walked S
:
This scenario forms a right triangle where distance between the boys is the hypotenuse
Using pythag: a^2 + b^2 = c^2

:
6.25t^2 + 9t^2 = 16
15.25t^2 = 16
t^2 = 
t^2 = 1.0492
t = 
t = 1.0243 hrs walking time for max range of the walkie-talkies
Then
2.5 * 1.0243 = 2.56 mi, T's walking dist for max range
and
3 * 1.0243 = 3.073 mi, S's walking dist
:
:
Check this on your calc enter  results: 3.9996 ~ 4 mi
|
Triangles/564633: My daughter has asked my help with her math and it has been a very long time since I have worked this kind of problem (below). Please help me with the proper formula to use in showing her how to work this type of problem. Thank you.
ABC is a 30-60-90 triangle with a right angle at B. Use the measure of the side given to find the measure of the indicated side.
BC= 20, find AB 1 solutions
Answer 365496 by ankor@dixie-net.com(15622) on 2012-01-30 08:26:37 (Show Source):
You can put this solution on YOUR website!BC is a 30-60-90 triangle with a right angle at B. Use the measure of the side given to find the measure of the indicated side.
BC= 20, find AB
:
We can use the tangent of 60 degrees to find side AB
That is: tan(60) = 
tan(60) = 
1.732 = 
AB = 1.732 * 20
AB = 34.64
|
Travel_Word_Problems/564616: Trains A and B leave the same city at right angles at the same time. Train B travels 5 mph faster than Train A. After 2 hours, they are 50 miles apart. Find the speed of each train. 1 solutions
Answer 365420 by ankor@dixie-net.com(15622) on 2012-01-29 22:00:19 (Show Source):
You can put this solution on YOUR website!Trains A and B leave the same city at right angles at the same time.
Train B travels 5 mph faster than Train A.
After 2 hours, they are 50 miles apart. Find the speed of each train.
:
let s = speed of train A
then
(s+5) = speed of train B
After 2 hrs:
train A dist = 2s
train B dist = 2(s+5)
:
We can treat this as a pythag, problem where a^2 + b^2 = c^2
Where
a = 2s
b = 2(s+5)
c = 50
:
(2s)^2 + (2(s+5))^2 = 50^2
4s^2 + (2s + 10)^2 = 2500
4s^2 + 4s^2 + 40s + 100 = 250
A quadratic equation
8s^2 + 40s + 100 - 2500 = 0
8s^2 + 40s - 2400 = 0
Simplify divide by 8
s^2 + 5s - 300 = 0
This will factor to
(s+20)(s-15) = 0
the positive solution
s = 15 mph is Train A
and
15 + 5 = 20 mph is train B
:
:
Check this on calc:
enter  results: 50
|
Linear-equations/564609: Please help me understand how to solve this.
t+m=2.10
2t+3m=5.15 1 solutions
Answer 365393 by ankor@dixie-net.com(15622) on 2012-01-29 20:42:54 (Show Source):
You can put this solution on YOUR website!t + m = 2.10
2t+3m = 5.15
:
We are going use elimination here:
multiply the 1st equation by 2 and subtract from the 2nd equation
2t + 3m = 5.15
2t + 2m = 4.20
---------------subtraction eliminates t, find m
0t + m = .95
m = .95
:
Find t using the 1st equation, replace m with .95
t + .95 = 2.10
t = 2.10 - .95
t = 1.15
:
:
Check our solution of t=1.15 and m=.95 in the 2nd equation
2t + 3m = 5.15
replace t and m
2(1.15) + 3(.95 =
2.30 + 2.85 = 5.15 which is correct
;
How about now, do you understand this?
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Surface-area/564557: A round pizza with a diameter of 52 cm is cut into 12 equal sectors. a square pizza,
with sides of length 41 cm, is cut into 9 equal squares. Which pizza slice, a sector
Or a square, has the greatest area and how much greater is it? Thank you so much
for your help and please use step by step if you can!!!(: 1 solutions
Answer 365391 by ankor@dixie-net.com(15622) on 2012-01-29 20:12:59 (Show Source):
You can put this solution on YOUR website!A round pizza with a diameter of 52 cm is cut into 12 equal sectors. a square
pizza, with sides of length 41 cm, is cut into 9 equal squares.
Which pizza slice, a sector Or a square, has the greatest area and how much
greater is it?
:
Find the area of the round pizza. 
r = 52/2 = 26 cm

A = 2123.7 sq/cm
Find the the area of each sector
 = 177 sq/cm for each sector
:
Find the area of the square pizza
 = 1681 sq/cm
Find the area of each of the 9 equal square
 = 187 sq/cm for the squares
:
187 - 177 = 10 sq/cm more in the square
|
Linear-systems/564462: Please solve the following system of linear equations with substitution.
3x-2=y
y-2x=-5 1 solutions
Answer 365386 by ankor@dixie-net.com(15622) on 2012-01-29 19:36:05 (Show Source):
You can put this solution on YOUR website!3x - 2 = y
y - 2x =-5
From the 1st equation we know that y = 3x - 2, therefore we can replace y with (3x-2) in the 2nd equation
(3x-2) - 2x = -5
3x - 2x = -5 + 2
x = -3
:
Find y
y = 3x - 2
we know x=-3
y = 3(-3) - 2
y = -9 - 2
y = -11
:
:
Check our solutions of x=-3, y=-11 in the 2nd equation
y - 2x = -5
replace x with -3, y with -11
-11 - 2(-3) = -5
minus a minus is a plus so we have
-11 + 6 = -5; which is true so our solution check out
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Money_Word_Problems/564182: a person walks a certain distance at a rate of 3.8mph, another person takes 2.1hrs longer to walk the same distance at a rate of 3.2mph. What distance did they walk? 1 solutions
Answer 365295 by ankor@dixie-net.com(15622) on 2012-01-29 11:15:47 (Show Source):
You can put this solution on YOUR website!a person walks a certain distance at a rate of 3.8mph, another person takes 2.1hrs longer to walk the same distance at a rate of 3.2mph.
What distance did they walk?
:
Let t = time for the faster person to walk the distance
then
(t+2.1) time for the slower person to walk it
:
Write a distance equation: dist = speed * time
they walk the same distance
:
3.8t = 3.2(t+2.1)
3.8t = 3.2t + 6.72
3.8t - 3.2t = 6.72
.6t = 6.72
t = 6.72/.6
t = 11.2 hrs
;
Find the distance using the faster time
11.2 * 3.8 = 42.56 mi
:
Check the distance using the slower time
13.3 * 3.2 = 42.56 mi
:
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Quadratic_Equations/564173: Hi, I am having a problem forming the equation from a worded problem. I am struggling to understand what the terms mean in this equation and how they worked them out. I understand how to solve and can write quadratic motion equations. I have a good understanding.
The problem is: A school concert usually attracts 600 people at a cost of $10 per person. On avaerage for every $1 rise in admission price, 50 less people attend the concert. If T is the total amount of takings and n is the number of $1 increases write a rule for the function which gives T in terms of n.
The answer is: T = 6000 + 100n -50n^2
My thinking is that the 6000 represents the miinmum of the independant variable 600 people at $10 each which totals $6000. So this is where the parabola will start from the y-axis (i.e at zero). But how did they get the 100n? What does this mean in the context of the problem and why n^2?
Why isn't it linear? Like T = 6000 - 50(n)
Your help would be appreciated. 1 solutions
Answer 365281 by ankor@dixie-net.com(15622) on 2012-01-29 10:21:52 (Show Source):
You can put this solution on YOUR website!A school concert usually attracts 600 people at a cost of $10 per person.
On average for every $1 rise in admission price, 50 less people attend the concert.
If T is the total amount of takings and n is the number of $1 increases write a rule for the function which gives T in terms of n.
The equation:
Total = no. of people * cost for each ticket
Which is
T(n) = (600-50n)*(10+n)
FOIL
T(n) = 6000 + 600n - 500n - 50n^2
The quadratic equation which has max value for some value of n
T(n) = -50n^2 + 100n + 6000
:
The parabola will look like this

Looks like max revenue will occur when n=1, 550 people and $11 ticket $6050
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Polynomials-and-rational-expressions/564032: solve the equation...(q+2/3)+(q-4/4)=2 I thought you would start by finding the LCM, which would be 12, but it is confusing me when it comes to the variables being added in. 1 solutions
Answer 365227 by ankor@dixie-net.com(15622) on 2012-01-28 21:04:06 (Show Source):
You can put this solution on YOUR website!solve the equation...(q+2/3)+(q-4/4)=2
:
 +  = 2
:
Multiply by the Lowest common denominator,
12*  + 12*  = 12(2)
Cancel the denominators and you have
4(q+2) + 3(q-4) = 24
:
4q + 8 + 3q - 12 = 24
7q - 4 = 24
7q = 24 + 4
7q = 28
q = 28/7
q = 4
:
:
See if that works in the original problem
 +  = 2
 +  = 2
2 + 0 = 2
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Travel_Word_Problems/563967: In a 5.00km race, one runner runs at a steady 12.0km/h and another runs at 14.0km/h. how fast from the finish line is the slower runner when the faster runner finishes the race? 1 solutions
Answer 365226 by ankor@dixie-net.com(15622) on 2012-01-28 20:50:13 (Show Source):
You can put this solution on YOUR website!In a 5.00km race, one runner runs at a steady 12.0km/h and another runs at 14.0km/h.
how "FAR" from the finish line is the slower runner when the faster runner finishes the race?
:
Find the time required by the faster runner to run the race
:
 hr to finish the race
:
Find how far the slower runner travels in 5/14 of an hr at 12 km/h
 * 12 = 4.2857 km
then
5.00 - 4.2857 ~ .7 km from the finish line when the faster runner finishes
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Travel_Word_Problems/563971: A freight train traveling at an average rate of 30 kilometers per hour is followed 2 hours later from the same station by a passenger train traveling at an average rate of 50 kilometers per hour. How many hours after the passenger train leaves will it pass the freight train? 1 solutions
Answer 365224 by ankor@dixie-net.com(15622) on 2012-01-28 20:42:06 (Show Source):
You can put this solution on YOUR website!A freight train traveling at an average rate of 30 kilometers per hour is followed 2 hours later from the same station by a passenger train traveling at an average rate of 50 kilometers per hour.
How many hours after the passenger train leaves will it pass the freight train.
:
Let t = travel time of the pass train
then
(t+2) = travel time of the freight
:
When the pass train catches the freight, they will have traveled the same distance
Write a distance equation; dist = speed * time
:
pass dist = freight dist
50t = 30(t+2)
50t = 30t + 60
50t - 30t = 60
20t = 60
t = 60/20
t = 3 hrs for the pass train to catch freight
:
:
see if that checks out both should travel the same dist
50(3) = 30(3+2)
150 = 150
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Travel_Word_Problems/563802: You jog at a speed of 6 miles per hour for 20 minutes, and you walk at a speed of 4 miles per hour for t minutes. If your combined jogging and walking distance is 3 miles, for how long did you walk?
1 solutions
Answer 365222 by ankor@dixie-net.com(15622) on 2012-01-28 20:30:10 (Show Source):
You can put this solution on YOUR website!You jog at a speed of 6 miles per hour for 20 minutes, and you walk at a speed of 4 miles per hour for t minutes.
If your combined jogging and walking distance is 3 miles, for how long did you walk?
:
We are dealing with mph, so we have to put the min over 60
:
Write a distance equation; dist = speed * time
:
Dist at 6mph + dist at 4mph = 3 miles
6*  + 4*  = 3
Cancel
 +  = 3
mult by 30 to clear the denominators, results
3(20) + 2t = 30(3)
60 + 2t = 90
2t = 90 - 60
2t = 30
t = 15 min at 4 mph
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logarithm/563657: use natural logarithms to solve the equation 7 (3^z) = 19 (15^z) for z (three decimal places) 1 solutions
Answer 365139 by ankor@dixie-net.com(15622) on 2012-01-28 09:50:17 (Show Source):
You can put this solution on YOUR website!use natural logarithms to solve the equation 7 (3^z) = 19 (15^z) for z (three decimal places)
:

divide both sides by 7

Divide both sides by 15^z

Which is

Reduce the fraction

using nat logs

log equiv of exponents

find the ln
-1.6094z = .9985
z = 
z = -.6206
:
:
Check solution on a calc:
enter 7*3^-.62) = 3.54
enter 19*15^-.62 = 3.54; confirms our solution of z = -.6206
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�t�e�s�t/563503: Two different schools (A and B) have the same number of pupils. The ratio of the boys in school A and the boys in school B is 2:1 and the ratio of the girls in school A and the girls in school B is 4:5. Find the ratio of the boys in school A to the girls in school A.
1 solutions
Answer 365059 by ankor@dixie-net.com(15622) on 2012-01-27 21:39:12 (Show Source):
You can put this solution on YOUR website!Two different schools (A and B) have the same number of pupils.
The ratio of the boys in school A and the boys in school B is 2:1 and the ratio of the girls in school A and the girls in school B is 4:5.
Find the ratio of the boys in school A to the girls in school A.
:
Let Ba = no. of boys in class A
Let Bb = no. of boys in class B
:
Let Ga = no. of girls in class A
Let Gb = no. of girls in class B
:
"Two different schools (A and B) have the same number of pupils."
Ba + Ga = Bb + Gb
:
"The ratio of the boys in school A and the boys in school B is 2:1"
 = 
cross multiply
2Bb = Ba
Bb = .5Ba
:
"and the ratio of the girls in school A and the girls in school B is 4:5."
 = 
cross multiply
4Gb = 5Ga
Gb =  Ga
Gb = 1.25Ga
:
We know that: Ba + Ga = Bb + Gb
replace Bb with .5Ba and Gb with 1.25Ga
Ba + Ga = .5Ba + 1.25Ga
Ba - .5Ba = 1.25Ga - Ga
.5Ba = .25Ga
multiply by 4, get rid of the decimals
2Ba = 1Ga
 = 
Find the ratio of the boys in school A to the girls in school A.
1:2, Boys to girls in school A
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Linear_Equations_And_Systems_Word_Problems/563573: When a bucket is filled 3/8 of its capacity its weight is 10 kg. If it is filled 3/5 of its capacity its weight is 14.5 kg. How much will its weight be when it is filled to the full capacity? 1 solutions
Answer 365039 by ankor@dixie-net.com(15622) on 2012-01-27 19:25:48 (Show Source):
You can put this solution on YOUR website!When a bucket is filled 3/8 of its capacity its weight is 10 kg.
If it is filled 3/5 of its capacity its weight is 14.5 kg.
How much will its weight be when it is filled to the full capacity?
:
We can convert these fractions to exact decimals
 = .375
 = .6
:
Assign the values as follows
x1 = .375; y1 = 10
x2 = .600; y2 = 14.5
:
Find the slope m = 
m =  =  = 20
:
Use the point/slope form to construct an equation: y - y1 = m(x - x1)
y - 10 = 20(x - .375)
y - 10 = 20x - 7.5
y = 20x - 7.5 + 10
y = 20x + 2.5, is the equation
:
Bucket is full when x = 1
y = 20(1) + 2.5
y = 22.5 kg for a full bucket
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Age_Word_Problems/563466: David is the age of 58 and Lisa is the age of 18. How long ago was David 5 times the age of Lisa.
Logically, I know the answer is 8 years ago since David would have been 50 and Lisa would have been 10 and 5*10 =50 which five times her age.
However, I need to come with this answer in an algebraic method and I've been wracking my brain over it. 1 solutions
Answer 365004 by ankor@dixie-net.com(15622) on 2012-01-27 16:57:02 (Show Source):
You can put this solution on YOUR website!David is the age of 58 and Lisa is the age of 18.
How long ago was David 5 times the age of Lisa.
:
let y = the no. years ago that D was 5 times L's age
:
58 - y = 5(18-y)
58 - y = 90 - 5y
-y + 5y = 90 - 58
4y = 32
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