- #1

dajohu

- 2

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Hi,

This is the problem:

Lorraine has $7.70 in dimes and quarters. If the number of quarters is two more than twice the number of dimes, how many of each type does she have?

I know the answer is 12 dimes and 26 quarters by figuring it in my head, but my professor requires us to show work to get credit of course and I can't come up with a working formula.

What I have so far figured is this:

25x + 20x + 20 + 10x - 10x = 770

45x = 750

x = 16.666... To me this won't work and I've been working on it for quite a while and can't really figure out what I'm doing wrong. I am using a formula that the professor went over in class, but like many other times, the problems we go over in class aren't quite like what we have for homework. I would appreciate any help anyone could offer.

Thanks

This is the problem:

Lorraine has $7.70 in dimes and quarters. If the number of quarters is two more than twice the number of dimes, how many of each type does she have?

I know the answer is 12 dimes and 26 quarters by figuring it in my head, but my professor requires us to show work to get credit of course and I can't come up with a working formula.

What I have so far figured is this:

25x + 20x + 20 + 10x - 10x = 770

45x = 750

x = 16.666... To me this won't work and I've been working on it for quite a while and can't really figure out what I'm doing wrong. I am using a formula that the professor went over in class, but like many other times, the problems we go over in class aren't quite like what we have for homework. I would appreciate any help anyone could offer.

Thanks

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