Two machines A and B. In one hour A makes 1000 products, B makes 700 products. Together they must take complete 12000 products in 8 hours. Suppose, B works 6.4 hours(with A then only A works). Then minimum how many hours does A work to finish the job?
I got the answer as 7.7. Just want to confirm. I don't have an OA for this
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umaa
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I got 1 hours 7 mins. Where did you get the question?ern5231 wrote:Two machines A and B. In one hour A makes 1000 products, B makes 700 products. Together they must take complete 12000 products in 8 hours. Suppose, B works 6.4 hours(with A then only A works). Then minimum how many hours does A work to finish the job?
I got the answer as 7.7. Just want to confirm. I don't have an OA for this
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sanjana
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1hr 7 min is the correct answer.
Explanation :
A
Rate : 1000 prod/hr
B
Rate : 700 prod/hr
Combined rate : 1700 prod/hr
They work together for 6.4 Hrs
Therefore,number of products produced in 6.4 hrs is
1700*6.4 = 10880 prod
Now A has to work alone to produce 12000-10880 = 1120 prods
Therefore
Rate : 1000 prod/hr
Work : 1120 prod
Hence,time = 1120/1000 = 1.12 Hrs = 67min = 1hr 7 min.
Explanation :
A
Rate : 1000 prod/hr
B
Rate : 700 prod/hr
Combined rate : 1700 prod/hr
They work together for 6.4 Hrs
Therefore,number of products produced in 6.4 hrs is
1700*6.4 = 10880 prod
Now A has to work alone to produce 12000-10880 = 1120 prods
Therefore
Rate : 1000 prod/hr
Work : 1120 prod
Hence,time = 1120/1000 = 1.12 Hrs = 67min = 1hr 7 min.
