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A machine produces nuts at 100 nuts/min and needs to be cleaned after
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15 May 2021, 23:12
15 May 2021, 23:12
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Question Stats:
74% (02:31) correct
25% (02:32) wrong based on 54 sessions
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A machine produces nuts at 100 nuts/min and needs to be cleaned after producing every 1000 nuts for 5 minutes . Another machine produces bolts at 75 bolts/min and needs to be cleaned after every 1500 bolts for 10 minutes.
A. The quantity in Column A is greater
B. The quantity in Column B is greater
C. The two quantities are equal
D. The relationship cannot be determined from the information given
Quantity A |
Quantity B |
Time (in minutes) required to produce 9000 pairs of nuts and bolts when both the machines start together |
130 |
A. The quantity in Column A is greater
B. The quantity in Column B is greater
C. The two quantities are equal
D. The relationship cannot be determined from the information given
Re: A machine produces nuts at 100 nuts/min and needs to be cleaned after
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16 May 2021, 09:23
16 May 2021, 09:23
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I think that the answer is A:
>Nut Machine:
rate: 100 nut/min
cleaning interval: 1000 nut / 1 cleaning
cleaning rate: 5 min/ 1 cleaning
>Bolt Machine:
rate: 75 bolt/min
cleaning interval: 1500 bolt / 1 cleaning
cleaning rate: 10 min/1 cleaning
9000 pairs nuts and bolts = 9000 nuts + 9000 bolts
Find max( minToComplete( nut,9000 ), minToComplete( bolt,9000 ) ):
minToComplete = min to clean + mins to produce
*production time "ends" after last obj. is produced, not last cleaning
>Nut Machine:
number cleanings = (9000 nut - 1000 nut)/ 1000 (nut/cleaning) = 8 cleanings
min to clean = 8 cleanings * (5 min / 1 cleaning) = 40 min
min to produce = 9000 nut * (1 min / 100 nut) = 90 min
min to complete = 40 min + 90 min = 130 mins
>Bolt Machine:
number cleanings = (9000 bolt -1500 bolt )/ 1500 (bolt/cleaning) = 5 cleanings
min to clean = 5 cleanings * (10 min / 1 cleaning) = 50 min
min to produce = 9000 bolt * (1 min / 75 bolt) = 120 min
min to complete = 50 min + 120 min = 170 min
***max(130, 170) = 170
so a total of 170 minutes is required to produce 9000 pairs of nuts and bolts when both machines start together (nut machine finishes first, bolt machine finishes 40 mins later).
A: 170
B: 130
Answer: A, Quantity A is greater
>Nut Machine:
rate: 100 nut/min
cleaning interval: 1000 nut / 1 cleaning
cleaning rate: 5 min/ 1 cleaning
>Bolt Machine:
rate: 75 bolt/min
cleaning interval: 1500 bolt / 1 cleaning
cleaning rate: 10 min/1 cleaning
9000 pairs nuts and bolts = 9000 nuts + 9000 bolts
Find max( minToComplete( nut,9000 ), minToComplete( bolt,9000 ) ):
minToComplete = min to clean + mins to produce
*production time "ends" after last obj. is produced, not last cleaning
>Nut Machine:
number cleanings = (9000 nut - 1000 nut)/ 1000 (nut/cleaning) = 8 cleanings
min to clean = 8 cleanings * (5 min / 1 cleaning) = 40 min
min to produce = 9000 nut * (1 min / 100 nut) = 90 min
min to complete = 40 min + 90 min = 130 mins
>Bolt Machine:
number cleanings = (9000 bolt -1500 bolt )/ 1500 (bolt/cleaning) = 5 cleanings
min to clean = 5 cleanings * (10 min / 1 cleaning) = 50 min
min to produce = 9000 bolt * (1 min / 75 bolt) = 120 min
min to complete = 50 min + 120 min = 170 min
***max(130, 170) = 170
so a total of 170 minutes is required to produce 9000 pairs of nuts and bolts when both machines start together (nut machine finishes first, bolt machine finishes 40 mins later).
A: 170
B: 130
Answer: A, Quantity A is greater
Re: A machine produces nuts at 100 nuts/min and needs to be cleaned after
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19 Nov 2022, 03:29
19 Nov 2022, 03:29
1
\(rt = w\)
For nuts, time would be
\(\frac{9000}{100}=90\) mins
Clean: every 1,000 nuts for 5 minutes so
9,000 nuts = \(9*5=45\)
Total time for nuts \(90+45=135\) minutes
For bolts, applied the same
\(\frac{9000}{45}=120\) minutes
Clean: every 1,500 bolts for 10 minutes
so, \(\frac{9000}{15}6\)
\(6*10=60\) minutes
Total time for bolts \(120+60=180\) minutes
However, it start at the same time so \(180-135=45\)
Total time \(135+45=180\) mins
Hence A since \(180>130\)
For nuts, time would be
\(\frac{9000}{100}=90\) mins
Clean: every 1,000 nuts for 5 minutes so
9,000 nuts = \(9*5=45\)
Total time for nuts \(90+45=135\) minutes
For bolts, applied the same
\(\frac{9000}{45}=120\) minutes
Clean: every 1,500 bolts for 10 minutes
so, \(\frac{9000}{15}6\)
\(6*10=60\) minutes
Total time for bolts \(120+60=180\) minutes
However, it start at the same time so \(180-135=45\)
Total time \(135+45=180\) mins
Hence A since \(180>130\)
