SOLUTION: 1. A cookie recipe calls for 1 7/8 of flour and 1 1/4 of sugar. A girl has plenty of flour but only 2 1/8 of sugar. How much flour should she use with the 2 1/8 cups for sugar to k

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Question 1003612: 1. A cookie recipe calls for 1 7/8 of flour and 1 1/4 of sugar. A girl has plenty of flour but only 2 1/8 of sugar. How much flour should she use with the 2 1/8 cups for sugar to keep the indegredients in proportion?
Found 2 solutions by stanbon, addingup:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
1. A cookie recipe calls for 1 7/8 of flour and 1 1/4 of sugar. A girl has plenty of flour but only 2 1/8 of sugar. How much flour should she use with the 2 1/8 cups for sugar to keep the indegredients in proportion?
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Use a proportion:
flour/sugar = flour/sugar
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f/(2 1/8) = (1 7/8)/(1 1/4)
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f/(17/8) = [15/8 / 5/4]
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f/(17/8) = 15/10
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f/(17/8) = 3/2
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f = (17/8)(3/2)
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flour = 51/16 = 3.1876 cups
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Cheers,
Stan H.
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Answer by addingup(3677) (Show Source):
You can put this solution on YOUR website!
I'm not sure I know what you need. She has more sugar (2 1/8 cups) than is needed for the recipe (1 14 cups). Are you saying she wants to use all the sugar she has? If that's the case:
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1 7/8:1 1/4 is the ratio.
15/8:5/4
= 15/8:10/8 A ratio is the same as a division:
(15/8)/(10/8) To divide you flip the second fraction and multiply:
= 15*8/8*10
= 120/80 Divide by 10:
12/8 Divide both sides by 4:
3/2 Now, 3 is bigger than 2: 3/2= 1 and you have a remainder of 1:
1 1/2. Your ratio is:
1:1 1/2 You need 1 1/2 parts of sugar for every 1 part of flour.