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July 7, 2015

July 7, 2015

Posted by **Ire** on Friday, February 17, 2012 at 10:36pm.

- math -
**yoyoma**, Saturday, February 18, 2012 at 1:46amThis is a logic problem. I will write out the steps below.

Ja= Jack

Ji= Jill

Jill gives 50 to Jack, so she has 50 less and he has 50 more.

And, this quantity of 50 more is equal to 5 times Jill's amount.

So, now Jill has Ji-50 and Jack has Ja + 50

So, now just think how to set this up algebraically: If they both had 100 to start with, and Jill gives away 50, she has 50 now, and Jack has 150. So, the difference between the two will always be 100, no matter what number you choose for the beginning value. So, Jill will have 100 less marbles than Jack now.

Ji= Ja- 100

Now we develop a new relationship:

Ja= 5 Ji

Ja= 5 ( Ja - 100)

Ja= 5Ja-500

Ja + 500= 5Ja

4Ja= 500

Ja= 125

Now solve for Ji using Ja= 5 Ji

125= 5 Ji

J= 25

Now since Jill gave him 50 and he took 50, you subtract 50 from his pile, and add 50 to hers.

So, Jill had 75 to begin with and Jack had 75 to begin with.

Check backwards:

75-50= 25= Ji now

75 + 50= 125= Ja now

Is this statement true: Ja= 5 Ji?

125= 5 * 25

125= 125

Yes! It is. So, this is your answer!

Hope this helps!

- math -
**Ire**, Saturday, February 18, 2012 at 6:21amThis is a question to the answer above

Got it. I was confused with the question because what if they did NOT start with the same amount but did receive same amount from grandpa? Is that a different problem or cannot be done?

- math -
**Ire**, Saturday, February 18, 2012 at 8:16pmYoyoma, can you please answer the question on what if Jack & Jill did NOT start with equal amount of marbles?