Jack spent $2040 of his savings on a hi-if set and 3/5 of the remainder on a display cupboard. If he had 1/4 of his original savings left, how much was his original savings?
x - 2040 = r
r - 3/5 r = 1/4 x
so
2/5 r = 1/4 x
r = 5/8 x
then
x - 2040 = 5/8 x
3/8 x = 2040
x = 5440
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check
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5440 - 2040 = 3400
3/5 (3400) = 2040 for cupboard
3400 - 2040 = 1360 left
1360 * 4 = 5440 whew :)