<span>Equation:
0.15x + 0.10(5-x) = 0.11*5
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Multiply thru by 100:
15x + 10*5 - 10x = 11*5
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5x = 5
x = 1 liter (amt. 15% oj needed)
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5-x = 4 liters (amt of 10% oj needed)
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V = x/t = 4.5 mil / 3 h = 1.5 mph
Since, v = 1.5 mph (or we can say that v is constant), distance and time vary directly and the constant of variation is 1.5 mph.
It is a hot summer day, and Jade is trying to save money to buy a new shoe. She has 32 dollars, and she plans to sell smoothies at her neighborhood for four dollars a cup. At the end of the day, she is left with a total of 164 dollars in her wallet. How many smoothies did Jade sell?