If you select a marble at random, the chances of it being yellow are 9/18.
If you selected another marble at random, without replacing the first marble, then 8/17 is the probability of getting another yellow marble. I subtracted 1 from the numerator and denominator of 9/18 to go to 8/17.
We multiply the two results
(9/18)*(8/17) = 0.235 approximately
There's roughly a 23.5% chance of getting two yellow in a row, where we don't replace the first marble selected.
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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