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josmiceli answered: 9678 problems
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absolute-value/573444: |3X| + 7 > 2
1 solutions

Answer 368767 by josmiceli(9680) About Me  on 2012-02-15 19:21:07 (Show Source):
You can put this solution on YOUR website!
+abs%283x%29+%2B+7+%3E+2+
Subtract 7 from both sides
+abs%283x%29+%3E+-5+
The left side will never be negative, so
any value of x satisfies this equation
-infinity < x < + infinity


Age_Word_Problems/573418: The sum of my age and my daughter's is 50 years. In 30 years, 3 times my age increased by my daughter's age will be equal to 242 years. How old are we today?
1 solutions

Answer 368762 by josmiceli(9680) About Me  on 2012-02-15 19:12:51 (Show Source):
You can put this solution on YOUR website!
Let +f+ = Father's age now
Let +d+ = Daughter's age now
+f+%2B+30+ = father's age 30 yrs from now
+d+%2B+30+ = Daughter's age 30 yrs from now
----------
given:
(1) +f+%2B+d+=+50+
(2) +3%2A%28+f+%2B+30+%29+%2B+d+%2B+30+=+242+
------------------
(1) +d+=+50+-+f+
Substitute (1) into (2)
(2) +3%2A%28+f+%2B+30+%29+%2B+50+-+f+%2B+30+=+242+
(2) +3f+%2B+90+-+f+%2B+80+=+242+
(2) +2f+=+242+-+170+
(2) +2f+=+72+
(2) +f+=+36+
and, since
(1) +d+=+50+-+f+
(1) +d+=+50+-+36+
(1) +d+=+14+
I am 36 and my Daughter is 14
check:
(2) +3%2A%28+f+%2B+30+%29+%2B+d+%2B+30+=+242+
(2) +3%2A%28+36+%2B+30+%29+%2B+14+%2B+30+=+242+
(2) +3%2A66+%2B+44+=+242+
(2) +198+%2B+44+=+242+
(2) +242+=+242+
OK


Numbers_Word_Problems/573420: The room numbers of two adjacent classrooms are consective odd numbers. If their sum is is is 464, find classroom numbers.
1 solutions

Answer 368761 by josmiceli(9680) About Me  on 2012-02-15 18:54:57 (Show Source):
You can put this solution on YOUR website!
If +n+ is the lower number classroom,
+n+%2B+2+ is the next higher odd number
+n+%2B+n+%2B+2+=+464+
+2n+=+464+-2+
+2n+=+462+
+n+=+231+
+n+%2B+2+=+233+
The classroom numbers are 231 and 233
check:
+231+%2B+233+=+464+
OK


Linear-equations/572907: write an equation of a line perpendicular to y-4x-8 that goes through the point(0,6)
1 solutions

Answer 368558 by josmiceli(9680) About Me  on 2012-02-14 21:16:17 (Show Source):
You can put this solution on YOUR website!
+y+-+4x+-+8+ is not an equation.
It needs an equals sign somewhere.


Miscellaneous_Word_Problems/572862: One pump can drain a pool in 11 minutes. When a second pump is also used, the pool only takes 8 minutes to drain. How long would it take the second pump to drain the pool if it were the only pump in use?
1 solutions

Answer 368556 by josmiceli(9680) About Me  on 2012-02-14 21:12:30 (Show Source):
You can put this solution on YOUR website!
Let +t+ = time in minutes for 2nd pump alone to drain pool
Add the rates of pumping of each pump to get
the rate of both pumping together
Rate of 1st pump:
+1%2F11+ ( 1 pool drained/ 11 min )
Rate of 2nd pump:
+1%2Ft+ ( 1 pool drained / t min )
---------------------------
+1%2F11+%2B+1%2Ft+=+1%2F8+
Multiply both sides by +88t+
+8t+%2B+88+=+11t+
+3t+=+88+
+t+=+29.333+
+.333%2A60+=+20+
the 2nd pump takes 29 min and 20 sec to drain pool by itself
check answer:
+1%2F11+%2B+1%2F29.333+=+1%2F8+
+.09091+%2B+.034091+=+.125+
+.125001+=+.125+
error due to rounding off


Average/572881: I have tried to work tyhis problem out every which way and just can not figure it out. There does not seem to be an example of this in my book.
Thank You,
Nick

Raquel is mixing lemon-lime soda and a fruit juice blend that is 45% juice. If she uses 3 quarts of soda how many quarts of fruit juice must be added to produce punch that is 30% juice?
1 solutions

Answer 368547 by josmiceli(9680) About Me  on 2012-02-14 20:51:18 (Show Source):
You can put this solution on YOUR website!
Let +x+ = quarts of fruit juice blend to be added
In words:
( quarts of juice ) / ( non-juice + juice ) = 30%
given:
+.45x+ = juice in fruit juice blend
-----------------------------
+.45x+%2F+%28+x+%2B+3+%29+=+.3+
+.45x+=+.3%2A%28+x+%2B+3+%29+
+.45x+=+.3x+%2B+.9+
+.15x+=+.9+
+x+=+6+
6 quarts of fruit juice blend must be added
check answer:
+.45%2A6+%2F+%28+6+%2B+3+%29+=+.3+
+.45%2A6+=+.3%2A9+
+2.7+=+2.7+
OK
Notice that I made the unknown " fruit juice BLEND"
That's the only way the problem makes sense to me.


Money_Word_Problems/572798: a tax exempt charity recieves a bill for $145.90 for a sump pump. the bill incorrectly included sales taxs of 5%. how much does the charity owe.
1 solutions

Answer 368504 by josmiceli(9680) About Me  on 2012-02-14 18:07:35 (Show Source):
You can put this solution on YOUR website!
Let +x+ = the bill without the tax. The bill
that the charity received was:
+x+%2B+.05x+=+145.9+
+1.05x+=+145.9+
+x+=+145.9+%2F+1.05+
You can calculate it


Problems-with-consecutive-odd-even-integers/572737: Can you please help me and show me how to translate this problem?
Twice the sum of two consecutive odd integers is 32. Find the integers.
1 solutions

Answer 368489 by josmiceli(9680) About Me  on 2012-02-14 15:58:23 (Show Source):
You can put this solution on YOUR website!
Call the smallest odd integer +n+
The next higher odd integer would be +n+%2B+2+
given:
+2%2A%28+n+%2B+n+%2B+2+%29+=+32+
+2%2A%28+2n+%2B+2+%29+=+32+
+4n+%2B+4+=+32+
+4n+=+28+
+n+=+7+
+n+%2B+2+=+9+
The integers are 7 and 9
check:
+2%2A%28+n+%2B+n+%2B+2+%29+=+32+
+2%2A%28+7+%2B+9+%29+=+32+
+2%2A16+=+32+
+32+=+32+
OK


logarithm/572732: How do I solve log base of 125 1/5?
1 solutions

Answer 368487 by josmiceli(9680) About Me  on 2012-02-14 15:53:26 (Show Source):
You can put this solution on YOUR website!
+x+=+log%28125%2C%281%2F5%29%29+
I can rewrite this as:
+125%5Ex+=+1%2F5+
+%285%5E3%29%5Ex+=+1%2F5+
+5%5E%283x%29+=+1%2F5+
Take the log to the base 5 of both sides
+log%28+5%2C%285%5E%283x%29%29%29+=+log%285%2C%281%2F5%29%29+
+3x+=+-1+
+x+=+-%281%2F3%29+


Numbers_Word_Problems/572722: Seven years ago, I was eleven times as old as my daughter. Now I am four times as old as she is. My age is ____.
1 solutions

Answer 368486 by josmiceli(9680) About Me  on 2012-02-14 15:43:16 (Show Source):
You can put this solution on YOUR website!
Let +a+ = my age now
Let +b+ = my Daughter's age now
+a+-+7+ = my age 7 yrs ago
+b+-+7+ = my Daughter's age 7 yrs ago
---------------------------------------------
(1) +a+-+7+=+11%2A%28+b+-+7+%29+
(2) +a+=+4b+
------------------
Substitute (2) into (1)
(1) +4b+-+7+=+11%2A%28+b+-+7+%29+
(1) +4b+-+7+=+11b+-+77+
(1) +7b+=+70+
(1) +b+=+10+
and
(2) +a+=+4b+
(2) +a+=+4%2A10+
(2) +a+=+40+
My age is 40
check answer:
(1) +a+-+7+=+11%2A%28+b+-+7+%29+
(1) +40+-+7+=+11%2A%28+10+-+7+%29+
(1) +33+=+11%2A3+
(1) +33+=+33+
OK






Travel_Word_Problems/572639: An airline offers daily flights between Chicago and Denver. The total monthly cost C (in millions of dollars) of these flights is modeled by
C=Square root of 0.2x + 1
where x is the number of passengers (in thousands). The total cost of the flights for June is 1.7 million dollars. How many passengers flew in June? (Round your answer to the nearest whole number.)

1 solutions

Answer 368478 by josmiceli(9680) About Me  on 2012-02-14 13:58:48 (Show Source):
You can put this solution on YOUR website!
+C+=+sqrt%28.2x+%29+%2B+1+
given:
+1.7+=+sqrt%28.2x%29+%2B+1+
+.7+=+sqrt%28.2x%29+
Square both sides
+.49+=+.2x+
+x+=+.49%2F.2+
+x+=+2.45+
+2.45%2A1000+=+2450+
2,450 passengers flew in June


Graphs/572657: How do you write an equation that is parallel to y=4x-3?
How do you write an equation that is perpendicular to y=4x-3?
1 solutions

Answer 368477 by josmiceli(9680) About Me  on 2012-02-14 13:33:33 (Show Source):
You can put this solution on YOUR website!
(1) Just change the +-3+ to any other number.
(2) Change the +4+ to +-%281%2F4%29+. You
can change -3+ or leave it alone


Rectangles/572658: How do you reduce 180x28 inches?
1 solutions

Answer 368476 by josmiceli(9680) About Me  on 2012-02-14 13:30:12 (Show Source):
You can put this solution on YOUR website!
Do you mean change it to feet?
+180%2F12+=+15+ ft
+28%2F12+=+2+%2B+1%2F3+ ft
+1%2F3+ ft is +%281%2F3%29%2A12+=+4+ inches
180 x 28 in2 = 15' x 2' 4"


Travel_Word_Problems/572643: Amanda runs 7 miles in 50 minutes.At the same same rate,how many miles would she run in 75 minutes?
1 solutions

Answer 368475 by josmiceli(9680) About Me  on 2012-02-14 13:13:36 (Show Source):
You can put this solution on YOUR website!
She runs +7%2F50+ of a mile in 1 minute
In 75 min, she runs +%287%2F50%29%2A75+=+10.5+
She runs 10.5 mi in 75 min


Money_Word_Problems/572650: final amount received at the end of 1 month that results from starting at 1 cent today which is doubled each day for 1 month assume to be
30 days
1 solutions

Answer 368474 by josmiceli(9680) About Me  on 2012-02-14 13:08:37 (Show Source):
You can put this solution on YOUR website!
1, 2, 4, 8, etc = +2%5E%28d-1%29
where d is the day of the month
+2%5E%2830-1%29+=+2%5E29+
+2%5E29+=+536870912+ cents which is
+536870912+%2F+100+ dollars
$5,368,709.12


Rate-of-work-word-problems/572652: Jcobo delivers twice as many papers as Dahlia, who delivers 100 more papers than Rashid. If all together 500 paper are delivered, how many papers does each child deliver?
1 solutions

Answer 368473 by josmiceli(9680) About Me  on 2012-02-14 13:01:44 (Show Source):
You can put this solution on YOUR website!
Call the number of papers they deliver
+j+, +d+, and +r+
given:
(1) +j+=+2d+
(2) +d+=+r+%2B+100+
(3) +j+%2B+d+%2B+r+=+500+
----------------------------
From(2)
+r+=+d+-+100+
Substitute (1) and (2) into (3)
(3) +2d+%2B+d+%2B+d+-+100+=+500+
(3) +4d+=+500+%2B+100+
(3) +d+=+600%2F4+
(3) +d+=+150+
and, since
(1) +j+=+2d+
(1) +j+=+2%2A150+
(1) +j+=+300+
and
(2) +r+=+d+-+100+
(2) +r+=+150+-+100+
(2) +r+=+50+
Jcobo delivers 300
Dahlia delivers 150
Rashid delivers 50




test/572651: Graph each function!
1- y=2x^2 - 8x+3
2- y= -(x+3)^2+4
1 solutions

Answer 368472 by josmiceli(9680) About Me  on 2012-02-14 12:50:40 (Show Source):
You can put this solution on YOUR website!
(1)+y=+2x%5E2+-+8x+%2B+3+
(2)+y=+-%28x%2B3%29%5E2+%2B+4+
Here are both plots

The one on the left is (2)
The one on the right is (1)


Word_Problems_With_Coins/572494: Ian has 75 cents in quarters, dimes, and nickels. He has at least one of each type of coin. How many coins could he have? elementary grade
1 solutions

Answer 368419 by josmiceli(9680) About Me  on 2012-02-13 23:38:03 (Show Source):
You can put this solution on YOUR website!
1 quarter, 1 dime and 1 nickel is
+25+%2B+10+%2B+5+=+40+ cents
2 quarters, 1 dime and 1 nickel is
+50+%2B+10+%2B+5+=+65+ cents
2 quarters, 2 dimes and 1 nickel is
+50+%2B+20+%2B+5+=+75+ cents
---------------------------------
Also, you could have:
2 quarters, 1 dime and 3 nickels is
+50+%2B+10+%2B+15+=+75+ cents





expressions/572447: A train runs x miles an hour and an automobile (x-y) miles an hour. How much longer will it take the automobile to run s miles than the train?
note. this is from an Algebraic Representation Exercises Algebra I High School 10th Grade
1 solutions

Answer 368400 by josmiceli(9680) About Me  on 2012-02-13 22:06:32 (Show Source):
You can put this solution on YOUR website!
Equation for train:
(1) +s+=+x%2At%5B1%5D+
Equation for car:
(2) +s+=+%28+x+-+y+%29%2A+t%5B2%5D+
--------------------
(1) +t%5B1%5D+=+s%2Fx+
and
(2) +t%5B2%5D+=+s%2F%28+x+-+y+%29+
+t%5B2%5D+-+t%5B1%5D+=+s%2F%28+x+-+y+%29+-+s%2Fx+
+t%5B2%5D+-+t%5B1%5D+=+s%2A%28+1%2F%28x-y%29+-+1%2Fx+%29+


Numbers_Word_Problems/571992: A 2 digit number exceeds twice the sum of its digits by 9, that number when reversed gives 8 times the sum of its digits. Find the number
1 solutions

Answer 368258 by josmiceli(9680) About Me  on 2012-02-13 04:51:37 (Show Source):
You can put this solution on YOUR website!
Let the 10's digit = +a+
Let the 1's digit = +b+
The number is +10a+%2B+b+
The number reversed is +10b+%2B+a+
--------------------------------
given:
(1) +10a+%2B+b+=+2%2A%28+a+%2B+b+%29+%2B+9+
(2) +10b+%2B+a+=+8%2A%28+a+%2B+b+%29+
--------------------------------------
(1) +10a+%2B+b+=+2a+%2B+2b+%2B+9+
(1) +10a+-+2a+%2B+b+-+2b+=+9+
(1) +8a+-+b+=+9+
and
(2) +10b+%2B+a+=+8%2A%28+a+%2B+b+%29+
(2) +10b+%2B+a+=+8a+%2B+8b+
(2) +7a+=+2b+
(2) +a+=+%282%2F7%29%2Ab+
Substitute this into (1)
(1) +8a+-+b+=+9+
(1) +8%2A%282%2F7%29%2Ab+-+b+=+9+
(1) +16b+-+7b+=+63+
(1) +9b+=+63+
(1) +b+=+7+
and, since
(2) +a+=+%282%2F7%29%2Ab+
(2) +a+=+%282%2F7%29%2A7+
(2) +a+=+2+
The number is 27
check:
+27+=+2%2A%28+2+%2B+7+%29+%2B+9+
+27+=+18+%2B+9+
+27+=+27+
and
+72+=+8%2A%28+2+%2B+7+%29+
+72+=+72+
OK


Linear-equations/571804: I started off the problem with -3(z-6)>2z-2
I simplified that down to -3z+18>2z-2
I'm not sure what to do from here?
1 solutions

Answer 368203 by josmiceli(9680) About Me  on 2012-02-12 20:19:16 (Show Source):
You can put this solution on YOUR website!
+-3z+%2B+18+%3E+2z+-+2+
Add +3z+ to both sides
+18+%3E+5z+-+2+
Add 2 to both sides
+20+%3E+5z+
Divide both sides by +5+
+4+%3E+z+
Rewrite it going from right to left
+z+%3C+4+
--------
Put +z+=+3.99+ into original equation
+-3%2A3.99+%2B+18+%3E+2%2A3.99+-+2+
+-11.97+%2B+18+%3E+7.98+-+2+
+6.03+%3E+5.98+
OK


Expressions-with-variables/571768: I am having alot of trouble with these types of questions..
y=7/6x+4
-x+y=1
1 solutions

Answer 368193 by josmiceli(9680) About Me  on 2012-02-12 19:16:06 (Show Source):
You can put this solution on YOUR website!
(1) +y+=+%287%2F6%29%2Ax+%2B+4+
(2) +-x+%2B+y+=+1+
------------------
There are different ways to solve
this. Usually, you will be asked
to solve it a certain way.
------------------
First, you must recognize them as
straight line, or linear, equations.
That's because you only see +x+
and +y+, and not +x%5E2+ or +y%5E2+
------------------
Then you should know that there are
2 accepted forms to put them in:
(a)
Standard form:
+ax+%2B+by+=+c+
Point-slope form:
+y+=+mx+%2B+b+
-------------
So, +y+=+%287%2F6%29x+%2B+4+ is in point-slope form
and +-x+%2B+y+=+1+ is in standard form
-------------
Get them both into standard form
(1) +y+=+%287%2F6%29%2Ax+%2B+4+
Multiply both sides by +6+
(1) +6y+=+7x++%2B+24+
Subtract +7x+ from both sides
(1) +-7x+%2B+6y+=+24+
------------------
Now they are both in standard form
Multiply both sides of (2) by 6
and subtract (2) from (1) ( change the signs and add )
(1) +-7x+%2B+6y+=+24+
(2) +6x+-+6y+=+-6+
+-x+=+18+
+x+=+-18+
and, since
(2) +-x+%2B+y+=+1+
(2) +-%28-18%29+%2B+y+=+1+
(2) +18+%2B+y+=+1+
(2) +y+=+-17+
The solution is ( -18, -17 )
check answer:
(1) +y+=+%287%2F6%29%2Ax+%2B+4+
(1) +-17+=+%287%2F6%29%2A%28-18%29+%2B+4+
Multiply both sides by 6
(1) +-102+=+-126+%2B+24+
(1) +-102+=+-102+
OK
-------
It isn't easy. Do lots of problems and
you'll get better at it.
Here's a plot of the 2 lines. The intersection
is the solution
+graph%28+600%2C+600%2C+-20%2C+4%2C+-20%2C+4%2C+%287%2F6%29%2Ax+%2B+4%2C+x+%2B+1+%29+


Miscellaneous_Word_Problems/571598: In February, the price charged by Friendly Flowers for roses was inversely proportional to the number of days before Valentine’s Day the order is placed. A dozen roses ordered 10 days before February 14 cost $12.00 while the same order placed five days before cost $24.00. What is the cost of a dozen roses ordered one day before Valentine’s Day?
1 solutions

Answer 368136 by josmiceli(9680) About Me  on 2012-02-12 12:24:58 (Show Source):
You can put this solution on YOUR website!
Let +p+ = price of roses +d+ days
before Valentine's Day.
given: +p+=+k%2A%281%2Fd%29+ where +k+ is
a constant called the " proportionality constant"
--------------------------------------
(1) +12+=+k%2A%281%2F10%29+
(2) +24+=+k%2A%281%2F5%29+
-------------------
(1) +120+=+k+
and
(2) +120+=+k+
I think the 2 examples were given just to show
that the relation between +p+ and +1%2Fd+
is a linear one.
When d+=+1+,
+p+=+k%2A%281%2F1%29+
+k+=+120+
+p+=+120%2A1+
+p+=+120+
a dozen roses cost $120 1 day before Valentine's Day
Here's the plot of +p+=+120%2A%281%2Fd%29+
with +d+ on the horizontal axis:
+graph%28+400%2C+400%2C+-2%2C+30%2C+-10%2C+130%2C+120%2A%281%2Fx%29+%29+
You can see the price goes way up when d is small


Functions/571611: Can someone please help with this?
f(x) = 3x^2 -2x
f(0)=
f(-1)=
f(2)=
1 solutions

Answer 368133 by josmiceli(9680) About Me  on 2012-02-12 12:05:41 (Show Source):
You can put this solution on YOUR website!
+f%28x%29+=+3x%5E2+-2x+
+f%280%29=+3%2A%280%29%5E2+-+2%2A0+
+f%280%29+=+0+
----------
+f%28-1%29=+3%2A%28-1%29%5E2+-+2%2A%28-1%29+
+f%28-1%29+=+3+-%28-2%29+
+f%28-1%29+=+3+%2B+2+
+f%28-1%29+=+5+
------------
+f%282%29=+3%2A2%5E2+-+2%2A2+
+f%282%29+=+3%2A4+-+4+
+f%282%29+=+12+-+4+
+f%282%29+=+8+


logarithm/571608: how to find log of 1.8*10^-7
1 solutions

Answer 368131 by josmiceli(9680) About Me  on 2012-02-12 12:00:43 (Show Source):
You can put this solution on YOUR website!
+log%28+1.8%2A10%5E%28-7%29+%29+
Use the rule:
+log%28+a%2Ab+%29+=+log%28a%29+%2B+log%28b%29+
--------------------------
+log%28+1.8+%29+%2B+log%28+10%5E%28-7%29+%29+
Use the rule:
+log%28+a%5Eb+%29+=+b%2Alog%28a%29+
---------------------
+log%28+1.8+%29+%2B+%28-7%29%2Alog%2810%29+
+.25527+-+7%2A1+
+-6.7447+
check answer:
On my Casio calculator,
+10%5E%28-6.7447%29+=+1.800114%2A10%5E%28-7%29+
I assume error is due to rounding off


Linear_Equations_And_Systems_Word_Problems/571547: it takes bob the boy scout 10 hours to paddle upstream against the current a distance of 15 miles. when he turn around he finds it only takes him 5 hours to 'paddle 22.5 miles with current. how fast is bob's boat going in still water and what is the speed of the current of the river?
1 solutions

Answer 368123 by josmiceli(9680) About Me  on 2012-02-12 09:10:16 (Show Source):
You can put this solution on YOUR website!
Let +s+ = speed of boat in still water in mi/hr
Let +c+ = speed of current in mi/hr
+s+-+c+ = speed of boat going against the current in mi/hr
+s+%2B+c+ = speed of boat going with the current in mi/hr
-------------
given:
Going upstream:
(1) +d%5B1%5D+=+%28+s+-+c+%29%2At%5B1%5D+
(1)+15+=+%28+s+-+c+%29%2A10+
Going downstream:
(2) +d%5B2%5D+=+%28+s+%2B+c+%29%2At%5B2%5D+
(2) +22.5+=+%28+s+%2B+c+%29%2A5+
-----------------
(1) +s++-+c+=+3%2F2+
(2) +s+%2B+c+=++4.5+
add the equations:
(2) +s+%2B+c+=++4.5+
(1) +s+-+c+=+3%2F2+
+2s+=+6+
+s+=+3+
and
(1) +s++-+c+=+3%2F2+
(1) +3++-+c+=+3%2F2+
(1) +-c+=+-1.5+
(1) +c+=+1.5+
The speed of the boat in still water is 3 mi/hr
The speed of the current is 1.5 mi/hr
check:
(1)+15+=+%28+s+-+c+%29%2A10+
(1) +15+=+%28+3+-+1.5+%29%2A10+
(1) +15+=+1.5%2A10+
(1) +15+=+15+
and
(2) +22.5+=+%28+s+%2B+c+%29%2A5+
(2) +22.5+=+%28+3+%2B+1.5+%29%2A5+
(2) +22.5+=+4.5%2A5+
(2) +22.5+=+22.5+
OK


Geometry_Word_Problems/571502: In a family, each boy has as many sisters as brothers, but each sister has only half as many sisters as brothers. how many children are in the family?
1 solutions

Answer 368101 by josmiceli(9680) About Me  on 2012-02-12 04:34:10 (Show Source):
You can put this solution on YOUR website!
Count the boy as 1
(1) +b+-+1+=+s+ is what the boy sees
Count each sister as 1
Each sister sees +s+-+1+ of her sisters
For her,
(2) +b+=+2%2A%28+s+-+1+%29+
-----------------------------
(2) +b+=+2s+-+2+
Substitute (1) into (2)
(2) +b+=+2%2A%28+b+-+1+%29+-+2+
(2) +b+=+2b+-+2+-+2+
(2) +b+=+4+
and
(1) +b+-+1+=+s+
(1) +4+-+1+=+s+
(1) +s+=+3+
------------------
There are 4 bothers and 3 sisters,
or 7 children
This works



decimal-numbers/571505: I have a homework problem that I unfortunately do not understand how to set up to get the answer. My question is to "express the given repeating decimal as a quotient of integers. If possible reduce to lowest terms." It is the repeating decimal 0.71...
1 solutions

Answer 368098 by josmiceli(9680) About Me  on 2012-02-12 04:17:19 (Show Source):
You can put this solution on YOUR website!
The number is +n+ = .717171 . . .
One you learn this, you will never forget it!
+100n+ = 71.717171 . . .
+n+ = .717171 . . .
+100n+-+n+=+71+
+99n+=+71+
+n+=+71%2F99+
Looks good on my calculator


Linear_Equations_And_Systems_Word_Problems/571508: hey can you please help me with this question
$540 is divided among three people. a,b,c, so that a gets three times as much as c, and b gets twice as much as c. how much does c get?
thanks
1 solutions

Answer 368095 by josmiceli(9680) About Me  on 2012-02-12 04:11:52 (Show Source):
You can put this solution on YOUR website!
+a+%2B+b+%2B+c+=+540+
+a+=+3c+
+b+=+2c+
-----------------
By substitution:
+3c+%2B+2c+%2B+c+=+540+
+6c+=+540+
+c+=+90+
and
+a+=+3c+
+a+=+3%2A90+
+a+=+270+
and
+b+=+2c+
+b+=+2%2A90+
+b+=+180+
a gets 270
b gets 180
c gets 90
check:
+a+%2B+b+%2B+c+=+540+
+270+%2B+180+%2B+90+=+540+
+540+=+540+
OK


Age_Word_Problems/571517: Cecile is now four times as old as daisy . Five years ago , the sum of their two ages was 45 . How old each now?
1 solutions

Answer 368093 by josmiceli(9680) About Me  on 2012-02-12 04:03:47 (Show Source):
You can put this solution on YOUR website!
+c+ = Cecile's age now
+d+ = Daisy's age now
+c+-+5+ = Cecile's age 5 yrs ago
+d+-+5+ = Daisy's age 5 yrs ago
-------------
given:
(1) +c+=+4d+
(2) +%28+c+-+5+%29+%2B+%28+d+-+5+%29+=+45+
Substitute (1) into (2)
(2) +4d+-+5+%2B+d+-+5+=+45+
(2) +5d+-+10+=+45+
(2) +5d+=+55+
(2) +d+=+11+
and, since
(1) +c+=+4d+
(1) +c+=+4%2A11+
(1) +c+=+44+
Cecile is 44 and Daisy is 11
check:
(2) +%28+44+-+5+%29+%2B+%28+11+-+5+%29+=+45+
(2) +39+%2B+6+=+45+
(2) +45+=+45+
OK


Linear_Equations_And_Systems_Word_Problems/571510: hey, would you please be able to help me with the following question
a student runs three times as fast as she walks. she walked for 3 hours and ran for 2 hours and altogether went 36km. what was her speed of walking
thanks
1 solutions

Answer 368091 by josmiceli(9680) About Me  on 2012-02-12 03:55:54 (Show Source):
You can put this solution on YOUR website!
Let +s+ = her speed walking in km/hr
+3s+ = her speed running in km/hr
Let +d+ = distance traveled walking in km
+36+-+d+ = distance traveled running in km
-----------------
Her equation walking:
(1) +d+=+s%2A3+
Her equation running:
(2) +36+-+d+=+3s%2A2+
--------------------
(2) +36+-+d+=+6s+
Substitute (1) into (2)
(2) 36+-+3s+=+6s+
(2) +9s+=+36+
(2) +s+=+4+
Her speed walking was 4 km/hr
check answer:
(1) +d+=+s%2A3+
(1) +d+=+4%2A3+
(1) +d+=+12+
and
(2) +36+-+d+=+3%2A4%2A2+
(2) +36+-+d+=+24+
(2) +d+=+12+
OK