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Bunuel
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A stamping machine produces 100 gaskets per hour. When this machine 15 Oct 2019, 06:58
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B
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92% (01:20) correct 8% (02:11) wrong based on 507 sessions

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A stamping machine produces 100 gaskets per hour. When this machine works with a newer machine, the two machines, working simultaneously and independently at their respective constant rates, produce a total of 2,000 gaskets in 8 hours. How many gaskets does the newer machine produce per hour?

(A) 125
(B) 150
(C) 160
(D) 175
(E) 200
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B
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A stamping machine produces 100 gaskets per hour. When this machine 15 Oct 2019, 07:57
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Bunuel
A stamping machine produces 100 gaskets per hour. When this machine works with a newer machine, the two machines, working simultaneously and independently at their respective constant rates, produce a total of 2,000 gaskets in 8 hours. How many gaskets does the newer machine produce per hour?

(A) 125
(B) 150
(C) 160
(D) 175
(E) 200
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Efficiency of Machine A = 100
Efficiency of Machine A + B is 2000/8 = 250

Thus, Efficiency of machine B is 150

Hence, Efficiency of the newer machine is 150, Answer must be (B)
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A stamping machine produces 100 gaskets per hour. When this machine 06 Apr 2020, 10:27
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Bunuel
A stamping machine produces 100 gaskets per hour. When this machine works with a newer machine, the two machines, working simultaneously and independently at their respective constant rates, produce a total of 2,000 gaskets in 8 hours. How many gaskets does the newer machine produce per hour?

(A) 125
(B) 150
(C) 160
(D) 175
(E) 200
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A stamping machine produces 100 gaskets per hour.
Rate of ORIGINAL machine = 100 gaskets per hour

When this machine works with a newer machine, the two machines, working simultaneously and independently at their respective constant rates, produce a total of 2,000 gaskets in 8 hours.
2,000 gaskets in 8 hours is the same as 250 gaskets PER HOUR
In other words: (rate of ORIGINAL machine) + (rate of NEW machine) = 250 gaskets PER HOUR

How many gaskets does the NEWER machine produce per hour?
Take: (rate of ORIGINAL machine) + (rate of NEW machine) = 250 gaskets PER HOUR
Substitute to get: (100 gaskets per hour) + (rate of NEW machine) = 250 gaskets PER HOUR
So, rate of NEW machine = 150 gaskets per hour

Answer: B

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Brent
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A stamping machine produces 100 gaskets per hour. When this machine 09 Apr 2020, 04:37
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Bunuel
A stamping machine produces 100 gaskets per hour. When this machine works with a newer machine, the two machines, working simultaneously and independently at their respective constant rates, produce a total of 2,000 gaskets in 8 hours. How many gaskets does the newer machine produce per hour?

(A) 125
(B) 150
(C) 160
(D) 175
(E) 200
Show more

In 8 hours, the old machine produces 100 x 8 = 800 gaskets. Therefore, the new machine must produce 2000 - 800 = 1200 gaskets in 8 hours. Thus, the rate of the new machine is 1200/8 = 150 gaskets per hour.

Answer: B
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A stamping machine produces 100 gaskets per hour. When this machine 18 Feb 2024, 19:14
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Rate1 + Rate2 = 2000
(8*100) + (8*x) = 2000
800+8x = 2000
x = 150
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