SOLUTION: Hi I was wondering if I could get a second opinion on this problem. Jack and jill had some money in the ratio of 5 to 2 respectively. They jointly paid for a restaurant bill in th

Question 1147259: Hi
I was wondering if I could get a second opinion on this problem. Jack and jill had some money in the ratio of 5 to 2 respectively. They jointly paid for a restaurant bill in the ratio of 2 to 1 respectively. If jill spent 1/5 of her money and jack had 126 dollars left, how much did the bill cost.
thanks
Answer by greenestamps(13203) (Show Source): You can put this solution on YOUR website!

The amounts they started with were Jack:Jill = 5:2, so
let 5x = amount Jack started with
let 2x = amount Jill started with

Note that is a standard way to start on a problem where a ratio of 5:2 is given.

The amounts they paid on the bill were Jack:Jill = 2:1, so
let 2y = what Jack paid
let y = what Jill paid

Jill spent 1/5 of her money:

[1]

Jack had $126 left:

[2]

That's two equations in x and y. Solve by any method you like.

With one equation specifically defining one variable in terms of the other, substitution seems appropriate.

The number that is asked for is the total of the bill (not the "cost of the bill"), which is 2y+y = 3y.

ANSWER: The bill was 3y = $36

-------------------------------------------------

Added after seeing the two responses from other tutors....

Both of the other responses had valid starts on the problem -- both of them very different from each other, and very different from mine. That's a good demonstration of the fact that there are almost always many different ways to set up a problem for solving.

Unfortunately in one of the responses a simple substitution was done incorrectly, leading to a wrong answer. It might be educational to look at the start of that response to see where the error was made and then follow that path to the final correct answer.
RELATED QUESTIONS
Hi jack and jill had some money in the ratio of 5:2. They jointly paid for a... (answered by josmiceli,MathTherapy)

I had a problem stating that I had to "Plot 0, -5 on my coordinate plane. Then, label the (answered by josgarithmetic)

i have had trouble working on this math problem and i was wondering if someone could help (answered by AnlytcPhil)

Hi Mandy and jack had some sweets in the ratio of 5:7.after mandy gave jack some sweets... (answered by ankor@dixie-net.com)

Jill and Jack play basketball. In the first game, Jill had a foul shot average of... (answered by stanbon)

I'm learning how to write my "results" in slope-intercept form. And I'm having a little... (answered by Edwin McCravy)

Hi there! Well I was wondering if I could please get some help finding the center and... (answered by MathLover1)

Hi, my name is Christy. Our professor passes out sheets in our class and I was wondering... (answered by Alan3354,jim_thompson5910)

Hi, I am wondering if I could get some help with this question?? Solve for r r^2 +... (answered by solver91311)