The answer : 3780 bolts
Explain
We first calculate the time taken to make nuts and then first number of bolts made in remaining times
Nuts to be made: 750
Nuts made per hour : 500
Time take making nuts = total nuts/ nuts per hour
750/500= 1.5 hours
Time taken making nuts : 1.5 hours
Total time : 8 pm -2 pm :6 pm
Time remaining : 6-15 = 4.5 hours
Time remaining: 4.5 hours
Bolts per hour = 840 bolts
Total bolts made
Time remaining x bolts per hour
840x4.5
= 3780 bolts
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