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Working alone at its constant rate, Machine A can produce 1,050 electr 23 Apr 2018, 06:00
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78% (02:16) correct 22% (02:48) wrong based on 227 sessions

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Working alone at its constant rate, Machine A can produce 1,050 electrical components in 5 hours. Machine B, working alone, can produce 1,050 electrical components in 15/2 hours. If the two machine work simultaneously for T hours and produce 1,050 electrical components, how many electrical components has Machine B produced at the end of T hours?

(A) 140
(B) 210
(C) 420
(D) 525
(E) 630
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C
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Working alone at its constant rate, Machine A can produce 1,050 electr 23 Apr 2018, 06:17
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Bunuel
Working alone at its constant rate, Machine A can produce 1,050 electrical components in 5 hours. Machine B, working alone, can produce 1,050 electrical components in 15/2 hours. If the two machine work simultaneously for T hours and produce 1,050 electrical components, how many electrical components has Machine B produced at the end of T hours?

(A) 140
(B) 210
(C) 420
(D) 525
(E) 630
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In 1 hour machine A produces 1050/5 = 210 components
In 1 hour machine B produces 1050/(15/2) = 140 components.

Machine B produces 140/(140+210) of the total production of machine A and B in 1 hour = 0.4 or 40%
Machine B will produce 0.4*1050 = 420 at the end of T hours. We do NOT need to calculate T to get our answer.

Hence option C = 420 is the answer.
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Working alone at its constant rate, Machine A can produce 1,050 electr 23 Apr 2018, 08:43
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Machine A produces 1050 machines in 5 hours. So 210 machine per hour

Machine B produces 1050 machines in 7.5 hours, so 140 machines per hour.

Working together they would produce 350(210+140) machines per hour

They would take 3 hours to produce 1050 machines when working together.

In 3 hours machine B would
Produce 420 machines (140 * 3)

Ans: Option C

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Working alone at its constant rate, Machine A can produce 1,050 electr 23 Apr 2018, 23:00
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Solution



Given:
• Machine A produces 1050 components in 5 hours
• Machine B produces 1050 components in 15/2 hours
• Together they produce 1050 components in T hours

To find:
• The number of components that B produces in T hours

Approach and Working:
• The ratio of the number of components produced by A and B in one hour = \(\frac{1050}{5}\): \(\frac{1050}{(15/2)}\) = 3:2
• Therefore, in producing 1050 units together, B will produce = 1050 * \(\frac{2}{5}\) = 420 units
Hence, the correct answer is option C.
Answer: C
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Working alone at its constant rate, Machine A can produce 1,050 electr 24 Apr 2018, 11:35
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Bunuel
Working alone at its constant rate, Machine A can produce 1,050 electrical components in 5 hours. Machine B, working alone, can produce 1,050 electrical components in 15/2 hours. If the two machine work simultaneously for T hours and produce 1,050 electrical components, how many electrical components has Machine B produced at the end of T hours?

(A) 140
(B) 210
(C) 420
(D) 525
(E) 630
Show more

The rate of Machine A is 1,050/5, and, therefore, its output after T hours is (1,050/5)T. The rate of Machine B is [1,050/(15/2)], and its output after T hours is [1,050/(15/2)]T. Since the two machines are working together, we can add their outputs to create the equation:

(1,050/5)T + [1,050/(15/2)]T = 1,050

210T + 140T = 1050

350T = 1050

T = 3

So, in 3 hours Machine B can produce:

1,050/(15/2) x 3 = 140 x 3 = 420 components.

Answer: C
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Working alone at its constant rate, Machine A can produce 1,050 electr 09 May 2018, 10:52
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A produce 210 in 1 hr
B produce 1050*2/15=140 in 1 hr

So A+B produce 350 in 1 hr
And 1050 in 3 hr

So B produce 140*3=420

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Working alone at its constant rate, Machine A can produce 1,050 electr 10 May 2018, 01:32
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Bunuel
Working alone at its constant rate, Machine A can produce 1,050 electrical components in 5 hours. Machine B, working alone, can produce 1,050 electrical components in 15/2 hours. If the two machine work simultaneously for T hours and produce 1,050 electrical components, how many electrical components has Machine B produced at the end of T hours?

(A) 140
(B) 210
(C) 420
(D) 525
(E) 630
Show more

Rate of Machine A = 1050/5 = 210 EC per hour

Rate of Machine B = 1050 * 2/15 = 140 EC per hour

Combined rate = 210 + 140 = 350 EC per hour

Work done by B in T hours = 1050/350 * 140

= 420 EC per hour

(C)
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Working alone at its constant rate, Machine A can produce 1,050 electr 30 Nov 2024, 06:09
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