Answer:
D
Step-by-step explanation:
Piano: 2 hours
Cello: 4 hours
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Actual practice on the piano = 5 hours.
Actual practice on the cello = x
2/4 = 5/x
Notice the piano hours are on the top of the fractions on both the left and the right. All proportions work that way.
Cross multiply
2x = 4* 5
2x = 20 Divide by 2
x = 10
