Laura spent 2/5 of her money. Now she has $18 left. How much money did she have originally?
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Answer:
30
Step-by-step explanation:
We formulate the equation 3/5x=18, as she spend 2/5, and so 18 is the 3/5 she has left. Now with 3/5x=18, we multiply each side by 5/3, leaving x=18*5/3, and that gives us 30