1) Change the word problem into an equation:
.5x+x=213.75 where x equal the amount of money Dave earns.
2) Combine the like terms: .5x+x=1.5x
3) Now solve: 1.5x=213.75 and use multiplicative inverse to get your answer of 142.5
4) Now wait, this is the amount Dave earns not the amount Monsiha earns, however we know that Monsiha earns half that, therefore:
142.5÷2=75.25
The answer would be 'Monsiha raised $75.25 in total'.
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