A company uses 2 machines to fill an order for 3,360 bottle caps. Mach

good question, solving under 2 mins is surely a task for this question where in so much info is given...


from the given details we can say that rate of machine A per hour is 180 and B 240

so lets say that both machines start off at same time:

so 1 to 4 hours : work of A + B = (180+240) * 4= 1680 caps

now from 5th,6th & 7th hrs machine A is off for calibration and 5th & 6th hr machine in 7th hr machine B starts off again and makes 240 caps more

total now is 1680+240 = 1920

starting 8th hour both A & B start working together but condition that B would work till 10th hour only..

8th hour A & B = 180+ 240 = 420 + 1920 = 2340
9th hour A & B= 420 + 2340 = 2760
10th hour A & B = 420 + 2760 = 3180
11th hour only A works = 180 + 3180 = 3360

so machine B has made :
240 * 8 hrs of total work = 1920 caps

IMO D