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At the local retirement home, a popular drink is CranOrange craze, a mixture of

ID: 3116709 • Letter: A

Question

At the local retirement home, a popular drink is CranOrange craze, a mixture of cranberry juice and orange juice. Betty likes her mixture to be 30% cranberry juice and 70% orange juice. Her husband Don likes his mixture to be 60% cranberry juice and 40% orange juice. Ethel is very picky, however, and she likes her mixture to be 53% cranberry and 47% orange. One day, Betty and Don visit Ethel’s apartment. Betty brings 6 quarts of her mixture and Don brings 4 quarts of his mixture. Ethel decides to mix them together. She then wants to add either pure cranberry juice or pure orange juice to make the resulting mixture 53% cranberry and 47% orange. How much and which kind of juice does she need to add? Using an algebraic equation?

Explanation / Answer

6 quarts of (30-70) juice have -

cranberry = 6*30% = 1.8

orange = 6*70% = 4.2

4 quarts of (60-40) juice have -

cranberry = 4*60% = 2.4

orange = 4*40% = 1.6

total cranberry = 1.8+2.4 = 4.2

total orange = 4.2+1.6 = 5.8

this mixture is 42%-58%.

to make it 53%-47%, clearly she has to add more of cranberry

47% is equal to 5.8

so 53% is equal to 5.8*53% /47% = 6.54

so additional 6.54-4.20 = 2.34 quarts of craneberry juice has to be added.