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Problem 1 Solution(a) 1.3333333 (b) 2.5 cups mix and 1.875 cups water (c) 16.66667 cups mix and 12.5 cups water Solution Steps for Part (a):What is the ratio of mix to water in each case?
Answer:We know from the table that the ratio of mix to water in each case is:
Notice that these ratios all reduce to the same decimal using a calculator, 1.3333333, which we may interpret as 1.3333333 parts mix to one part water ( 1.3333333 : 1 ). Notice that order is important in a ratio; the convention is to put the first quantity  for us the mix amount  in the numerator (top of fraction) and the second  the water  in the denominator (bottom).
Solution Steps for Part (b):What quantities of mix and water should be used if we want to make 15 pancakes?
Answer:There are several ways to figure this answer. Here is how to use a proportion to get it. We know from the first row of the table that the ratio of mix to pancakes is 1 : 6. We can get the amount of mix for 15 pancakes using a proportion:
Notice that we've used x for the unknown amount of mix. Cross multiplying this gives:
So we need 2.5 cups of mix for 15 pancakes. How much water? Using the ratio we found above for mix to water, 1.3333333, and solving: 1.3333333 x = 2.5 x = 2.5 1.3333333 = 1.875.
Solution Steps for Part (c):What quantities of mix and water should be used if we want to make 100 pancakes?
Answer:Using the same technique as above: We know from the first row of the table that the ratio of mix to pancakes is 1 : 6. We can get the amount of mix for 100 pancakes using a proportion:
So we need 16.666667 cups of mix for 100 pancakes. How much water? Using the ratio we found above for mix to water, 1.3333333, and solving:
1.3333333 x = 16.666667 x = 12.5

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