this post was submitted on 11 Nov 2023
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Riddles

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Answer these riddles and the esophagus will let you pass.

Riddles for 'Lemmy'winks.

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The Check (catata.fish)
submitted 1 year ago by [email protected] to c/[email protected]
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A woman went into a bank to cash an insurance refund check. By mistake the teller gave her dollars for cents and cents for dollars. She put the money in her purse but accidentally dropped a nickel on the floor. When she got home, she found that she had exactly twice the amount of the check she had cashed. She didn't have any money in her wallet before going to the bank. What was the exact amount of that check?

AnswerThe amount must have been $31.63. She received $63.31. After she dropped a nickel there would remain the sum of $63.26, which is twice the amount of the check.

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[–] vatlark 1 points 1 week ago* (last edited 1 week ago) (1 children)

If x is the dollar amount written on the check and y is the cents amount.

The original check amount was: x+y The amount that teller handed the lady was: 100y+x/100 The amount the lady found in her bag was: 100y + x/100 - 0.05

We know the lady found twice the amount of the original check: 2(x+y) = 100y + x/100 - 0.05

They want you to solve for the original check amount x+y.

I messed up my algebra somewhere because I got: x=(5+9800y)/199 which if you set y = 0.63 you get x = 31.05 so I'm off somewhere.

[–] vatlark 1 points 1 week ago* (last edited 1 week ago) (1 children)

I wasn't too far off, I dropped a minus sign somewhere. expanded form from Wolfram alpha: 199x/100 -98y +0.05 =0

[–] vatlark 1 points 1 week ago* (last edited 1 week ago)

I can't think of a mathematical way to constrain x to be positive integers and constrain y to be any integer 0 to 99 divided by 100. Using a graph was a good idea