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#1 2007-04-18 08:36:34

Joseph
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Tough math problem

I'm having a really tough time solving this problem and could use some help!

Shomika was helping her family pick oranges in their grove.  She took some oranges home to share with her three friends.  She gave 3 more than half to Jennifer.  Angela got half of the remainder and 3 more.  She gave Josie half of the remainder plus 3.  When she got home, she had only 10 oranges left.  How many did she have when she left the grove?

#2 2007-04-18 09:09:37

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: Tough math problem

It’s an iterative problem:

where a[sub]n[/sub] is the number of oranges Shomika has left after giving to the nth person, and a[sub]3[/sub] = 10. So you just work backwards and find a[sub]0[/sub].

(a[sub]0[/sub] = 122.)

PS:

Last edited by JaneFairfax (2007-04-18 09:35:37)


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#3 2007-04-19 02:28:57

George,Y
Member
Registered: 2006-03-12
Posts: 1,306

Re: Tough math problem

Simplier way:
Shomika got 3 less than the same half of Josie.
So the half is 13
Before giving Josie the remainder is 26.
26 is 3 less than the previous half.
The previous remainder is 2(26+3)=58
Thus the original amount is 2(58+3)=122

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#4 2007-04-19 02:41:16

JaneFairfax
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Registered: 2007-02-23
Posts: 6,868

Re: Tough math problem

That’s exactly my method above.

I like to generalize. roll


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A: Click here for answer.

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