PS Practice test question #10

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Source: — Problem Solving |

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by mals24 » Fri Aug 29, 2008 7:18 am
IMO D

machine A seals k/8 cartons in 1 hr
machine B seals k/4 cartons in 1 hr

together they seal k/4+k/8=3k/8 in 1 hour

hence the percent of cartons sealed by faster machine ie mach B will be

(k/4)/(3k/ 8 ) = 8/12 = 2/3 = 66(2/3)%

Option D

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by somail » Fri Aug 29, 2008 8:29 am
You can also solve this one by picking a number for K. This works as K is constant between the two machines.

K=50

50 boxes in 8 hrs
50 boxes in 4 hrs

If the two worked together for 4 hours, we would have 25 + 50 boxes produced. Total boxes equals 75 with the faster machine making 50 of them. 50/75 = 2/3 = 66(2/3)%