Answer: 14
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Explanation:
In Rona's sample, she got 16 green out of 16+24 = 40 total.
So 16/40 = (8*2)/(8*5) = 2/5 of the results she got were green.
Assuming this ratio is kept the same, this would mean 2/5 of the 35 marbles in the box should be green. This is the value we expect though realistically it might be slightly off.
2/5 of 35 = (2/5)*35 = (2*35)/5 = 70/5 = 14
We should expect 14 of the marbles in the box to be green.
