Answer:
7. (17/5)*(8/3)
8. 24
Explanation:
7. Dividing by a number is the same as multiplying by its inverse (reciprocal). The divisor is 3/8, so the same result is obtained by multiplying by 8/3. The answer to this division problem is the same as the answer to the multiplication problem ...
(3 2/5) ÷ (3/8) = (3 2/5)*(8/3) = (17/5)*(8/3)
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8. The ratio of chocolate to not-chocolate cupcakes is ...
40% : (1 -40%) = 40% : 60% = 2 : 3
Multiplying by 12, we see the ratio of chocolate to not-chocolate is ...
2 : 3 = 24 : 36
24 cupcakes were chocolate.
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You could solve for c, the number of cupcakes, using ...
36 = (1 -40%)c = 0.60c
36/0.60 = c = 60
Then, you could find the number of chocolate cupcakes with ...
chocolate = 40%×c = 0.40×60 = 24