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Monica spent of her money and another $5 on prawns.
She then spent of the remaining money and another $3 on chickens.
Finally, she spent of what was left and another $2 on vegetables.
She was left with $1.50 in the end. How much money did she have at first?
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Solve the problem in a backward manner.
For it, represent Monica spendings by steps.
(1) She spent of her money and another $5 on prawns.
(2) She then spent of the remaining money and another $3 on chickens.
(3) Finally, she spent of what was left and another $2 on vegetables.
(4) She was left with $1.50 in the end.
It means that immediately before step (3), she had (1.50 + 2)*2 = 3.50*2 = 7 dollars.
Hence, immediately before step (2), she had (7 + 3)*2 = 10*2 = 20 dollars.
It means that immediately before step (1), she had (20+5)*2 = 25*2 = 50 dollars.
So, at first, Monica had 50 dollas. ANSWER
You can check my answer by moving from the beginning to the end.
Solved.