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?
Answer
The 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.
I’m interested, how else would you find the solution besides plugging in a guess and adjusting up or down until it works?
I think it’d have multiple solutions so it’d just be an algebraic formula right?
x.(y-5) = 2(y.x)
solve for x, plot graph, pick positions where both x and y stop at the hundredths column.
been a minute since over had to think about this stuff so maybe did that wrong lol
Yeah, it’s been too long for me too. I came up with the same first formula, was looking at it not really wanting to solve for X or try to find my graphing calculator when I realized it still wouldn’t land just on appropriate solutions, and wondered if there was a better way. But once it is graphed, yeah, finding where the solutions don’t go past the hundredths column works.
Your response also made me think of looking for a graphing calculator app again. I did once a frightening number of years ago and didn’t find much and I never thought of it again, haha!