Bob gave 4/5 of his pencils to Barbara, then he gave 2/3 of the remaining pencils to Bonnie. If he ended up with 10 for his self, how many did he start with?
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x = initial amount
Bob gave 4/5 of X away so he has 1/5 of X left
Bob gave 2/3 of remaining so Bob has 1/3 of remaining which looks like this (1/3)*(1/5x) = 1/15x
Bob now has 10 pencils left so
1/15x = 10 // Multiply both sides by 15
x = 150
Bob gave 4/5 of X away so he has 1/5 of X left
Bob gave 2/3 of remaining so Bob has 1/3 of remaining which looks like this (1/3)*(1/5x) = 1/15x
Bob now has 10 pencils left so
1/15x = 10 // Multiply both sides by 15
x = 150
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Bob started with 150 pencils :)
The way to answer this question is to work backwards:
1/3 of the pencils that he didn't give to bonnie was 10, so before he gave some to bonnie he had 30. So 1/5 is 30 therefore 30 x 5 is 150.
The way to answer this question is to work backwards:
1/3 of the pencils that he didn't give to bonnie was 10, so before he gave some to bonnie he had 30. So 1/5 is 30 therefore 30 x 5 is 150.