Answer: 10 minutes
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Work Shown:
A = 50 = number of words typed in 1 minute
B = 1 minute
C = 500 words
D = x minutes (needed to type 500 words)
A/B = C/D
50/1 = 500/x
50*x = 1*500 ... cross multiply
50x = 500
x = 500/50 .... divide both sides by 50
x = 10
You'll need 10 minutes to type 500 words
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Alternative approach:
50 words = 1 minute .... given speed
1 word = 1/50 minute ... divide both sides by 50
1 word = 0.02 minute
500 words = 10 minutes .... multiply both sides by 500
