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How Much Money 2
How much money would I have had if, in spending 1/5 and then 1/5 of the remaining, I had altogether spent $36.00?
Answer
$100.Hide Answer Show Answer
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clever question!
Cute teaser!
While it's an easy math problem, you should still explain the answer.
1/5 + (1/5)*(4/5) = 9/25
25/9 * 36 = 100
1/5 + (1/5)*(4/5) = 9/25
25/9 * 36 = 100
Let x = original amount of money
x/5 + (4/5x)/5 = 36 (total amount of money spent, in terms of x)
5/25x + 4/25x = 36
9/25x = 36
x = 36 * 25/9
x = 100
x/5 + (4/5x)/5 = 36 (total amount of money spent, in terms of x)
5/25x + 4/25x = 36
9/25x = 36
x = 36 * 25/9
x = 100
If x = original amount:
0.2x + 0.2*0.8x = 36
0.2x + 0.16x = 36
0.36x = 36
x = 36/0.36
x = 100
0.2x + 0.2*0.8x = 36
0.2x + 0.16x = 36
0.36x = 36
x = 36/0.36
x = 100
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