Question

Chris and Diane each opened a savings account today. Chris opened his account with a starting amount of $650, and he is going to take out $40 per month. Diane opened her account with a starting amount of $850, and she is going to take out $65 per month. Let x be the number of months after today. ​

Answer 1

Incomplete question, but see below for an educated guess.

Explanation:

There was more to this question, let me see if I can figure it out.

Was it something like, "How long until Chris/Diane is out of money?" Or, "When will Diane's account value match Chris's?"

Let's take the first one: When will Chris be out of money?

He starts with $650 and takes out (sounds like subtraction) $40 for x months (sounds like multiplication).

Would this work?

650 - 40x = 0

I think so, because it will tell us how many months (x) are needed to multiply by the 40 to subtract from the 650 each month until it's all gone. Let's solve for x. First add 40x to each side to make it easier to work with:

650 = 40x See how that worked?

Now how do we get x by itself? Divide by 40, you say?

x = 650/40 = 16.25 months

So in that number of months, 16 months and about 7 days, Chris's money will be gone.

You can do the same for Diane, just change the two numbers.

I won't tackle the other problem I proposed unless you come back and say that's what they wanted. Be good.