Proportion Problem

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Proportion Problem

by phoenix9801 » Thu May 31, 2012 2:29 pm
A machine at a golf ball factory can produce 16 golf balls in 5 minutes. If several of these machines work independently and each machine performs at the same rate, how many machines are needed to produce 32 golf balls per minute?

A) 3
B) 6
C) 8
D) 10
E) 13

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by aneesh.kg » Thu May 31, 2012 8:52 pm
phoenix9801 wrote:A machine at a golf ball factory can produce 16 golf balls in 5 minutes. If several of these machines work independently and each machine performs at the same rate, how many machines are needed to produce 32 golf balls per minute?

A) 3
B) 6
C) 8
D) 10
E) 13
Rate because of one machine = 16/5 balls per minute
If there are n machines working together, the rate becomes 'n' times of the rate of one such machine.
Combined Rate = 16n/5 balls per minute

Given:
16/5n = 32
n = 10

[spoiler](D)[/spoiler] is correct.
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by Anurag@Gurome » Thu May 31, 2012 9:13 pm
phoenix9801 wrote:A machine at a golf ball factory can produce 16 golf balls in 5 minutes. If several of these machines work independently and each machine performs at the same rate, how many machines are needed to produce 32 golf balls per minute?
16 balls in 5 minutes ---> 1 machine
16 balls in 1 minute ---> 1*5 = 5 machines
32 balls in 1 minute ---> 5*2 = 10 machines

The correct answer is D.
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