See tutors' answers!

Algebra ->  Tutoring on algebra.com -> See tutors' answers!      Log On


   
By Tutor
 | By Problem Number | 

Tutor:
New! Get regular updates about newly solved problems via algebra.com's RSS system.

Recent problems solved by 'mananth'

mananth answered: 12270 problems
Jump to solutions: 0..29 , 30..59 , 60..89 , 90..119 , 120..149 , 150..179 , 180..209 , 210..239 , 240..269 , 270..299 , 300..329 , 330..359 , 360..389 , 390..419 , 420..449 , 450..479 , 480..509 , 510..539 , 540..569 , 570..599 , 600..629 , 630..659 , 660..689 , 690..719 , 720..749 , 750..779 , 780..809 , 810..839 , 840..869 , 870..899 , 900..929 , 930..959 , 960..989 , 990..1019 , 1020..1049 , 1050..1079 , 1080..1109 , 1110..1139 , 1140..1169 , 1170..1199 , 1200..1229 , 1230..1259 , 1260..1289 , 1290..1319 , 1320..1349 , 1350..1379 , 1380..1409 , 1410..1439 , 1440..1469 , 1470..1499 , 1500..1529 , 1530..1559 , 1560..1589 , 1590..1619 , 1620..1649 , 1650..1679 , 1680..1709 , 1710..1739 , 1740..1769 , 1770..1799 , 1800..1829 , 1830..1859 , 1860..1889 , 1890..1919 , 1920..1949 , 1950..1979 , 1980..2009 , 2010..2039 , 2040..2069 , 2070..2099 , 2100..2129 , 2130..2159 , 2160..2189 , 2190..2219 , 2220..2249 , 2250..2279 , 2280..2309 , 2310..2339 , 2340..2369 , 2370..2399 , 2400..2429 , 2430..2459 , 2460..2489 , 2490..2519 , 2520..2549 , 2550..2579 , 2580..2609 , 2610..2639 , 2640..2669 , 2670..2699 , 2700..2729 , 2730..2759 , 2760..2789 , 2790..2819 , 2820..2849 , 2850..2879 , 2880..2909 , 2910..2939 , 2940..2969 , 2970..2999 , 3000..3029 , 3030..3059 , 3060..3089 , 3090..3119 , 3120..3149 , 3150..3179 , 3180..3209 , 3210..3239 , 3240..3269 , 3270..3299 , 3300..3329 , 3330..3359 , 3360..3389 , 3390..3419 , 3420..3449 , 3450..3479 , 3480..3509 , 3510..3539 , 3540..3569 , 3570..3599 , 3600..3629 , 3630..3659 , 3660..3689 , 3690..3719 , 3720..3749 , 3750..3779 , 3780..3809 , 3810..3839 , 3840..3869 , 3870..3899 , 3900..3929 , 3930..3959 , 3960..3989 , 3990..4019 , 4020..4049 , 4050..4079 , 4080..4109 , 4110..4139 , 4140..4169 , 4170..4199 , 4200..4229 , 4230..4259 , 4260..4289 , 4290..4319 , 4320..4349 , 4350..4379 , 4380..4409 , 4410..4439 , 4440..4469 , 4470..4499 , 4500..4529 , 4530..4559 , 4560..4589 , 4590..4619 , 4620..4649 , 4650..4679 , 4680..4709 , 4710..4739 , 4740..4769 , 4770..4799 , 4800..4829 , 4830..4859 , 4860..4889 , 4890..4919 , 4920..4949 , 4950..4979 , 4980..5009 , 5010..5039 , 5040..5069 , 5070..5099 , 5100..5129 , 5130..5159 , 5160..5189 , 5190..5219 , 5220..5249 , 5250..5279 , 5280..5309 , 5310..5339 , 5340..5369 , 5370..5399 , 5400..5429 , 5430..5459 , 5460..5489 , 5490..5519 , 5520..5549 , 5550..5579 , 5580..5609 , 5610..5639 , 5640..5669 , 5670..5699 , 5700..5729 , 5730..5759 , 5760..5789 , 5790..5819 , 5820..5849 , 5850..5879 , 5880..5909 , 5910..5939 , 5940..5969 , 5970..5999 , 6000..6029 , 6030..6059 , 6060..6089 , 6090..6119 , 6120..6149 , 6150..6179 , 6180..6209 , 6210..6239 , 6240..6269 , 6270..6299 , 6300..6329 , 6330..6359 , 6360..6389 , 6390..6419 , 6420..6449 , 6450..6479 , 6480..6509 , 6510..6539 , 6540..6569 , 6570..6599 , 6600..6629 , 6630..6659 , 6660..6689 , 6690..6719 , 6720..6749 , 6750..6779 , 6780..6809 , 6810..6839 , 6840..6869 , 6870..6899 , 6900..6929 , 6930..6959 , 6960..6989 , 6990..7019 , 7020..7049 , 7050..7079 , 7080..7109 , 7110..7139 , 7140..7169 , 7170..7199 , 7200..7229 , 7230..7259 , 7260..7289 , 7290..7319 , 7320..7349 , 7350..7379 , 7380..7409 , 7410..7439 , 7440..7469 , 7470..7499 , 7500..7529 , 7530..7559 , 7560..7589 , 7590..7619 , 7620..7649 , 7650..7679 , 7680..7709 , 7710..7739 , 7740..7769 , 7770..7799 , 7800..7829 , 7830..7859 , 7860..7889 , 7890..7919 , 7920..7949 , 7950..7979 , 7980..8009 , 8010..8039 , 8040..8069 , 8070..8099 , 8100..8129 , 8130..8159 , 8160..8189 , 8190..8219 , 8220..8249 , 8250..8279 , 8280..8309 , 8310..8339 , 8340..8369 , 8370..8399 , 8400..8429 , 8430..8459 , 8460..8489 , 8490..8519 , 8520..8549 , 8550..8579 , 8580..8609 , 8610..8639 , 8640..8669 , 8670..8699 , 8700..8729 , 8730..8759 , 8760..8789 , 8790..8819 , 8820..8849 , 8850..8879 , 8880..8909 , 8910..8939 , 8940..8969 , 8970..8999 , 9000..9029 , 9030..9059 , 9060..9089 , 9090..9119 , 9120..9149 , 9150..9179 , 9180..9209 , 9210..9239 , 9240..9269 , 9270..9299 , 9300..9329 , 9330..9359 , 9360..9389 , 9390..9419 , 9420..9449 , 9450..9479 , 9480..9509 , 9510..9539 , 9540..9569 , 9570..9599 , 9600..9629 , 9630..9659 , 9660..9689 , 9690..9719 , 9720..9749 , 9750..9779 , 9780..9809 , 9810..9839 , 9840..9869 , 9870..9899 , 9900..9929 , 9930..9959 , 9960..9989 , 9990..10019 , 10020..10049 , 10050..10079 , 10080..10109 , 10110..10139 , 10140..10169 , 10170..10199 , 10200..10229 , 10230..10259 , 10260..10289 , 10290..10319 , 10320..10349 , 10350..10379 , 10380..10409 , 10410..10439 , 10440..10469 , 10470..10499 , 10500..10529 , 10530..10559 , 10560..10589 , 10590..10619 , 10620..10649 , 10650..10679 , 10680..10709 , 10710..10739 , 10740..10769 , 10770..10799 , 10800..10829 , 10830..10859 , 10860..10889 , 10890..10919 , 10920..10949 , 10950..10979 , 10980..11009 , 11010..11039 , 11040..11069 , 11070..11099 , 11100..11129 , 11130..11159 , 11160..11189 , 11190..11219 , 11220..11249 , 11250..11279 , 11280..11309 , 11310..11339 , 11340..11369 , 11370..11399 , 11400..11429 , 11430..11459 , 11460..11489 , 11490..11519 , 11520..11549 , 11550..11579 , 11580..11609 , 11610..11639 , 11640..11669 , 11670..11699 , 11700..11729 , 11730..11759 , 11760..11789 , 11790..11819 , 11820..11849 , 11850..11879 , 11880..11909 , 11910..11939 , 11940..11969 , 11970..11999 , 12000..12029 , 12030..12059 , 12060..12089 , 12090..12119 , 12120..12149 , 12150..12179 , 12180..12209 , 12210..12239 , 12240..12269 , 12270..12299, >>Next

Angles/346961: The supplement of an angle is 36 degrees less than twice the supplement of the complement of the angle. Find the measure of the supplement. Can you also explain it too? Thank you so much
1 solutions

Answer 248109 by mananth(12270) About Me  on 2010-09-22 21:24:13 (Show Source):
You can put this solution on YOUR website!
let the angle be x degrees
the supplement of this angle will be 180-x
..
The complement of the angle will be 90-x
supplement of this complement angle will be 180 - (90-x)
Twice this = 2[180-(90-x)]
Less 36
=2[180-(90-x)]-36
..
180-x = 2[180-(90-x)]-36
...
180-x= 2[180-90+x]-36
180-x=2[90+x]-36
180-x=180+2x-36
3x=180-180+36
3x=36
x= 12
supplement of 12 = 180-12 = 168


Travel_Word_Problems/346953: A bullet is fired horizontally at a target, and the sound of its impact is heard 1.5 seconds later. If the speed of the bullet is 3300 ft/sec and the speed of sound is 1100 ft/sec how far away is the target?
1 solutions

Answer 248100 by mananth(12270) About Me  on 2010-09-22 21:15:05 (Show Source):
You can put this solution on YOUR website!
let target distance be x
bullet speed = 3300ft/sec
sound speed = 1100 ft/sec
sound heard after 1.5 seconds = 3/2
..
x/3300 + x/ 1100 = 3/2
LCD = 3300
x+3x /3300 = 3/2
4x/3300 = 3/2
4x= 3*3300/2
4x=9900/2
4x= 4950
x= 4950/4
x=1237.5 feet


Expressions-with-variables/346948: find the values of the variables (3x-40) (2x-10)
1 solutions

Answer 248087 by mananth(12270) About Me  on 2010-09-22 21:05:54 (Show Source):
You can put this solution on YOUR website!
(3x-40) (2x-10)
If (3x-40) (2x-10)=0
Then 3x=40
x=40/3
OR
2x-10=0
2x=10
x=5


Graphs/346945: what is the x and y intercept of -3x+8y=48
1 solutions

Answer 248083 by mananth(12270) About Me  on 2010-09-22 20:59:07 (Show Source):
You can put this solution on YOUR website!
-3x+8y=48
..
for x intercept y=0
-3x+0=48
x=48/-3
x=-16..
For y intercept x=0
0+8y=48
8y=48
y=6


Triangles/346942: 1.) The perimeter of a triangle is 76 centimeters. The second side is twice as long as the first side. The third side is four centimeters shorter than the second side. How long is each side?
1 solutions

Answer 248080 by mananth(12270) About Me  on 2010-09-22 20:56:03 (Show Source):
You can put this solution on YOUR website!
let first side be x
second side= = 2x
third side= 2x-4
...
x+2x+2x-4=76
5x-4=76
5x=76+4
5x=80
x=16 cm first side
second side = 2*16= 32 cm
third side = 2x-4 = 2*16 -4 =28 cm


Equations/346938: A pasta machine cost $33.oo and the ingredients to make one batch of pasta costs .33. One batch of pasta bought in a store costs .99.
How many batches of pasta will you have to make for the cost of the machine and ingredients to equal the cost of buying the same amount of pasta at the store.
1 solutions

Answer 248073 by mananth(12270) About Me  on 2010-09-22 20:46:35 (Show Source):
You can put this solution on YOUR website!
Let the number of batches be x
cost of x batches = 0.33x
cost of machine = 33
cost of x batches in store = 0.99x
0.33x+33=0.99x
0.99x-0.33x=33
0.66x=33
x=33/0.66
x= 50 batches of pasta.


Equations/346934: You earn $9 per hour. On major holidays, such as Thanksgiving, you earn twice as much per hour. You earned a total of $405 for the week including thanksgiving. Write and solve an equation to find how many hours you worked on thanksgiving if you worked 35 hours during the rest of the week.
1 solutions

Answer 248067 by mananth(12270) About Me  on 2010-09-22 20:38:28 (Show Source):
You can put this solution on YOUR website!
thanks giving day x hours
..
other days 35-x hours
..
earning = 9*(35-x) on normal day
Thanksgiving day - 18x
..
18x+9(35-x)=405
18x+315-9x = 405
9x=405-315
9x=90
x=10 hours on Thanksgiving day


test/346925: at 9:00 on Saturday two bicyclist heading in opposite directions pass each other on a bicycle path. the bicyclist heading north is riding 6km/hr faster than the bicyclist heading south. at 10:15,they are 42.5km apart. find the two bicyclists rates.
1 solutions

Answer 248064 by mananth(12270) About Me  on 2010-09-22 20:29:55 (Show Source):
You can put this solution on YOUR website!
at 9:00 two bicyclist heading in opposite directions
the bicyclist heading south x km/h
bicyclist heading north x+6 km/hr.
at 10:15,= 1 1/4 hour = 5/4 hours
they are 42.5km apart.
.....
5/4 *x +5/4 *(x+6) = 42.5
5x/4+(5x+30) /4 =42.5
(5x+5x+30)=4*42.5
10x+30=170
10x=170-30
10x=140
x=14 km/h south
14 +6 = 20km/h north bound


Surface-area/346549: Finding the area of a rectangle when the length is v+3 and the width is 5, the answer is 5v + 15. I understand how I arrived at 15 but I don't understand the 5v part.
Thank you
1 solutions

Answer 247755 by mananth(12270) About Me  on 2010-09-22 02:22:26 (Show Source):
You can put this solution on YOUR website!
length = v+3
width =5
Area A = L*W
A= 5*(v+3)
A= 5*v+5*3
A=5v+15


Finance/346550: An investment of $37,000 was deposited in the bank. Interest was computed on a semi-annual basis and was kept there for 10 years. If the maturity value of this investment is $74,000, at what interest rate was it invested?
1 solutions

Answer 247754 by mananth(12270) About Me  on 2010-09-22 02:04:47 (Show Source):
You can put this solution on YOUR website!
Investment = 37000
FV= 74,000
years = 10
compunded semi annual =2
number of periods = 2*10 = 20
r=%28FV%2FPV%29%5E%281%2Fn%29+-1
r=+%28%2874000%2F37000%29%5E%281%2F20%29%29-1%29
r=0.0352
=7.052% /year


Travel_Word_Problems/346537: the bus travel at 30mph left city at 10:30 am the car follow at 50mph leave at 12 noon at what time the car catch up with the bus?
1 solutions

Answer 247752 by mananth(12270) About Me  on 2010-09-22 00:17:52 (Show Source):
You can put this solution on YOUR website!
Bus 10.30 30mph
car 12.00 50mph
...
the bus has already traveled 30*1.5 = 45 miles when car starts.
the car catches up 50-30 = 20 mph
It has to catch up 45 miles
45/20 = 2.25 hours
add 2.25 hours to 12.00
.25*60=15 minutes
...
it catches up at 2.15 p.m


Graphs/346520: graph this system: 2x + y > 2
x - y < 1
1 solutions

Answer 247750 by mananth(12270) About Me  on 2010-09-21 23:38:35 (Show Source):
You can put this solution on YOUR website!
2x + y > 2
y>-2x+2......................1
x - y < 1
add y
x-y+y>y+1
x>y+1
add -1
(x-1>y)
y Assume an equal to sign instead of < or >.
For both the equations find values of y for 3 or more values of x.
graph%28300%2C300%2C-3%2C3%2C-3%2C3%2C%28-2x%2B2%29%2C%28x-1%29%29
The red line indicates graph 1
In this equation y > something
so all values above the line are solutions.
and green line for equation 2.
y< something so all points below the graph are solutions


Geometry_Word_Problems/346515: Find the area of a rectangle that has a base of (4a) cm and a height of (2a b) cm.
1 solutions

Answer 247749 by mananth(12270) About Me  on 2010-09-21 23:21:35 (Show Source):
You can put this solution on YOUR website!
Area of triangle = 1/2 * base * height
A= 1/2 *4a * 2ab
A= 2a*2ab
A=4a^2b sq.cm


Angles/346493: the measure of an angle is 20 degrees less than three times its supplement. find the measure of each angle
1 solutions

Answer 247731 by mananth(12270) About Me  on 2010-09-21 21:56:33 (Show Source):
You can put this solution on YOUR website!
let angle be x
supplement = 180-x
x = 3(180-x)-20
x=540-3x-20
3x+x=540-20
4x=520
x=130
supplement = 50 deg


Complex_Numbers/346490: 1/a+1/b=c
solve for a
1 solutions

Answer 247730 by mananth(12270) About Me  on 2010-09-21 21:52:10 (Show Source):
You can put this solution on YOUR website!
1/a+1/b=c
1/a= c - 1/b
1/a= (bc-1)/b
take reciprocal
a=b/(bc-1)


Functions/346473: 7/x^2-x-6+5/x-3
1 solutions

Answer 247729 by mananth(12270) About Me  on 2010-09-21 21:49:37 (Show Source):
You can put this solution on YOUR website!
7%2F%28x%5E2-x-6%29%2B5%2F%28x-3%29
7%2F%28%28x-3%29%28x%2B2%29%29%2B+5%2F%28x-3%29
LCD = (x-3)(x+2)
%287%2B5%28x%2B2%29%29%2F%28x-3%29%28x%2B2%29
%285x%2B17%29%2F%28x-3%29%28x%2B2%29


test/346481: Easy as it might seem, I have forgotten how to take a simple number and turn it into a decimal.

so if I want to turn 392 to the third decimal place what is the easiest way to do this?
Thanks :o)
1 solutions

Answer 247728 by mananth(12270) About Me  on 2010-09-21 21:39:42 (Show Source):
You can put this solution on YOUR website!
divide by 1000
392/1000 = 0.392
...
25/100 = 0.25
..
2/10 = 0.2


real-numbers/346478: -7-3[2+(5-8)]
1 solutions

Answer 247727 by mananth(12270) About Me  on 2010-09-21 21:37:44 (Show Source):
You can put this solution on YOUR website!
_7-3[2+(5-8)]
-7-3[2+(-3)]
-7-3[2-3]
-7-3[-1]
-7+3
-4


Miscellaneous_Word_Problems/346443: a gardener is reseeding a city park that has a shape of a right triangle with a base of 150 ft, height of 200 ft, and 250 ft long
a) one bag of grass seed covers 3750 sq ft and cost 27.50 how many bags are needed and what is the total cost?
b) wire fencing cost $23.19 for each 50 ft rl how much does it cost to buy fencing to enclose the area?
c) fence posts cost $3.19 ea & needs to be placed every 5 ft how many posts are needed and what is the cost all together?
1 solutions

Answer 247722 by mananth(12270) About Me  on 2010-09-21 21:08:42 (Show Source):
You can put this solution on YOUR website!
a gardener is reseeding a city park that has a shape of a right triangle with a base of 150 ft, height of 200 ft, and 250 ft long
a) one bag of grass seed covers 3750 sq ft and cost 27.50 how many bags are needed and what is the total cost?
..
Area of triangle = 1/2 *base * height
A= 1/2 * 150*200
A= 15000 sq. ft
1 bag 3750 sq.ft
15000 = ?
15000/3750 = 4 bags
1 bag = $27.50
4 bags = 4*27.50= $110
....
b) wire fencing cost $23.19 for each 50 ft rl how much does it cost to buy fencing to enclose the area?
Perimeter P = sum of all sides = 150+200+250=600 feet
50 ft = 23.19
600 ft = 600*23.19
wire fensing cost =$13914
...
c) fence posts cost $3.19 ea & needs to be placed every 5 ft how many posts are needed and what is the cost all together?
Perimeter = 600 feet
posts are kept 5ft apart
600/5= 120 posts
1 post = 3.19
120 posts = 119*3.19= $379.61

Add up all the three


Travel_Word_Problems/346433: mike and adam left a bus terminal at the same time and traveled in opposite directions. Mike's bus was in heavy traffic and had to travel 20mi/hr slower than adams's bus. After 3 hours their buses were 270 miles apart. How fast was each bus going
1 solutions

Answer 247717 by mananth(12270) About Me  on 2010-09-21 20:53:46 (Show Source):
You can put this solution on YOUR website!
let adam's bus speed be x mph
mike's bus speed = x-20 mph
..
They are going in opposite directions
.
the effective speed = x+x-20
2x-20 mph.
Time = distance /speed
distance = 270 miles
3= 270/2x-2
3(2x-2)=270
6x-6=270
6x=276
x=276/6
x=46 mph adam's bus speed
mike's bus speed = 46-20 =26 mph


Linear-systems/346438: the sum of john and harry's ages is 19 years. if the difference of their ages is 5 years,what are their ages?
1 solutions

Answer 247711 by mananth(12270) About Me  on 2010-09-21 20:48:19 (Show Source):
You can put this solution on YOUR website!
x+y=19
x-y=5
add the two equations
2x=19+5
2x=24
/2
x=12
y=7


Rectangles/346436: How do I solve for x when the area of the rectangle is 30 and the length is 3x+1 and the width is x?
1 solutions

Answer 247706 by mananth(12270) About Me  on 2010-09-21 20:46:10 (Show Source):
You can put this solution on YOUR website!
Area of rectangle = L*W
30=(3x+1)*x
30=3x^2+x
3x^2+x-30=0
3x^2+10x-9x-90=0
3x(x+10)-9(x+10)=0
(x+10)(3x-9)=0
3(x+10)(x-3)=0
x=3


Matrices-and-determiminant/346098: I need to find the intersecting points of two equations: y=.15x and y=.2(x-20)and graph them. I have included my problem and what is expected. I'm lost.
Ok this is what I got :
You would set the two equations equal to each other and solve for x
.15x=.2(x-20) using the Elimination Method
Reorder the terms:
0.15x = 0.2(-20 + x)
0.15x = (-20 * 0.2 + x * 0.2)
0.15x = (-4 + 0.2x)
Solving
0.15x = -4 + 0.2x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-0.2x' to each side of the equation.
0.15x + -0.2x = -4 + 0.2x + -0.2x
Combine like terms: 0.15x + -0.2x = -0.05x
-0.05x = -4 + 0.2x + -0.2x
Combine like terms: 0.2x + -0.2x = 0.0
-0.05x = -4 + 0.0
-0.05x = -4
Divide each side by '-0.05'.
x = 80
Simplifying
x = 80
Now that X = 80, I plugged it into the equation y=0.15x and got this:
y=0.15x
y=0.15(80)
y= 12
Now this is the question to my problem and I do not know how to get the answer. I have to graph this and show the intersection.
a teacher is looking for the best option in purchasing school supplies for a classroom. Where Company A is offering a discount for every dollar amount spent on school supplies and where Company B is offering a higher discount than Company A, but the discount for Company B is only offered for every dollar amount spent above $20.00. I will determine and explain which company will offer a better price based upon the dollar amount the teacher spends on school supplies.
Option 1- Company A will offer her a 15% discount on the total amount spent in the store.
Option 2- Company B will offer her a 20% discount on the remaining amount after the first $20 is spent.
Depict the situation graphically, using appropriate graphing software such as Excel or an online graphing utility.
Include the following in your graph:
• A depiction of each cost option on the same graph
• Clear labels of the cost to the hypothetical customer for both options on the graph
• The intersection of the cost options (if one exists)
I'm so lost. I do not know how to graph this. Please help if you can.
1 solutions

Answer 247486 by mananth(12270) About Me  on 2010-09-21 10:49:56 (Show Source):
You can put this solution on YOUR website!
y=0.15x
(10,1.5)(20,3)(30,4.5)
y=0.2x-4
(20,0)(30,2)(40,4)
Your intersection values of (80,12) is correct.
for each equation
take 3 values of x and calculate y
plot the two graphs
graph%28300%2C300%2C-1%2C100%2C-1%2C15%2C0.15x%2C0.2x-4%29
you will get 2 graphs as above
...


Percentage-and-ratio-word-problems/346091: if you borrowed money at 15% simple interet after paying it off in one year your finally payoff was $1199.45 what was the original amount borrowed?
1 solutions

Answer 247479 by mananth(12270) About Me  on 2010-09-21 10:26:03 (Show Source):
You can put this solution on YOUR website!
Principal = p
rate = 15% = 0.15
I = 1199.55
....
1199.45 = p*0.15*1
1199.45/0.15 = p
p= 7,996.33


Travel_Word_Problems/346073: The winning sailboat completed a 24-mile race at an average speed of 9 miles/hour. The second-place boat finished with an average speed of 8 miles/hour. How many minutes longer than the winner did the second-place boat take to finish the race ?
A 20 min B 33 min C 60 min D 120 min

1 solutions

Answer 247450 by mananth(12270) About Me  on 2010-09-21 09:33:58 (Show Source):
You can put this solution on YOUR website!
time taken by winner = 24/9 hours
=2.66 hours
time taken by second boat = 24/8 hours
=3 hours
3-2.66= 0.0.34 hour
...
0.34 * 60 = 20.4 minutes
Option A


Mixture_Word_Problems/346068: a merchant has coffee worth $20 a pound that she wishes to mix with 90 pounds of coffee worth $60 a pound to get a mixture that can be sold for $30 a pound. How many pounds of the $20 coffee should be used?
1 solutions

Answer 247447 by mananth(12270) About Me  on 2010-09-21 09:27:32 (Show Source):
You can put this solution on YOUR website!
coffee $20 a pound x lbs
90 pounds of coffee worth $60 a pound
mixture x+90 lbs $30 a pound.
...
20x+90*60=30(x+90)
20x+5400=30x+2700
30x-20x=5400-2700
10x=2700
/10
x= 2700/10
x= 270 lbs of $20


Inequalities/346067: A gas station owner makes a profit of 40 cents per gallon of gas he sells. How many gallons must he sell in order to make a profit of $30,000?

1 solutions

Answer 247440 by mananth(12270) About Me  on 2010-09-21 09:17:39 (Show Source):
You can put this solution on YOUR website!
let the number of gallons he sells be x
he makes a profit of 40 cents per gallon = $ 0.4
0.4* x = total profit = 30000
x=30000/0.4
x=75000 gallons


Linear_Equations_And_Systems_Word_Problems/346052: A cyclist leaves his training base for a morning workout, riding at the rate of 20 mph. One hour later, his support staff leaves the base in a car going 36 mph in the same direction. How long will it take the support staff to catch up with the cyclist once the car leaves the base?

1 solutions

Answer 247438 by mananth(12270) About Me  on 2010-09-21 09:12:58 (Show Source):
You can put this solution on YOUR website!
cyclist speed = 20 mph
so in 1 hour he is ahead by 20 miles.
..
car speed = 36 mph
..
the car atches up 36-20 =16 mph
they have to catch up 20 miles
20/16 = time to catch up
1.25 hours


Inequalities/346055: Solve the compound inequality of - 9 < b/8 < 0 and write the solution set in interval notation.
1 solutions

Answer 247436 by mananth(12270) About Me  on 2010-09-21 09:09:09 (Show Source):
You can put this solution on YOUR website!
-9+%3C+b%2F8+%3C+0
multiply by 8
-9%2A8%3Cb%2F8+%2A8+%3C0%2A8
..
-72%3Cb%3C0
..
(-72,0)


Inequalities/346063: A long distance telephone service charges 10 cents for the first minute and 5 cents for each minute thereafter. Write an equation representing the cost C for any call, using x for its length. Using that equation, how many minutes can you talk on the phone if you don’t want the cost to exceed $5.00?

1 solutions

Answer 247431 by mananth(12270) About Me  on 2010-09-21 09:02:27 (Show Source):
You can put this solution on YOUR website!
x mins duration
5 cents/minute
5x per cal
+ 10 cents
...
C= 5x+10
....
5x+10<500 cents
add -10
5x<500-10
5x<490
/5
5x/5 = 490/5
x<98 minutes


Miscellaneous_Word_Problems/346018: Water weighs about 62.5 lbs. per cubic foot, and there is about 7.5 gallon in a cubic foot. If a 10-gallon can weighs 16 lbs. when empty, how many cans of water can be hauled in one-ton truck?
thank you!
1 solutions

Answer 247410 by mananth(12270) About Me  on 2010-09-21 05:28:40 (Show Source):
You can put this solution on YOUR website!
7.5 gallons weigh 62.5 lbs
10 gallons will weigh 62.5 *10/7.5
=83.3 lbs.
weight of 10 gallon water + weight of 10 gallon empty can =
=83.3 +16 = 99.3 pounds
..
1 ton = 2200 lbs
number of cans will be 1 ton/99.3
2000/99.3
= 20.14
OR 20 cans.