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xerocoool
Students
 
Posts: 63
Joined: Fri Aug 24, 2012 9:54 am
 

Q8) Manhattan 5lbs : Word Problems

by xerocoool Mon Sep 29, 2014 5:38 pm

Hi Tommy,

Q) A washing machine takes 35 mins to wash one load of laundry, and in between washing different loads of laundry it takes Derek 2 mins to unload and another 4 mins to reload the machine. If the washing machine begins washing one load of laundry at 12:30 PM, how many loads of laundry can Derek wash and unload before 6:35 PM ?

A) 8
B) 9
C) 10
D) 14
E) 15

12:30 PM to 6:30 PM = 6 hours = 360 mins
+ additional 5 mins to 6:35 PM => 365 mins

Wash + Load + Reload = (35 mins + 2 mins + 4 mins) = 41 mins

41 * 8 = 328 => 8 full cycles

365 - 328 = 37 mins still remaining

In the solution they have considered an additional cycle (from the remaining 37 mins). But the question says before 6:35 PM

35 mins for the wash + Last 2 min to load.

But does it not coincide with 6:35 pm ? (the last 2 mins of loading).

Thanks
xero
tommywallach
Manhattan Prep Staff
 
Posts: 1917
Joined: Thu Mar 31, 2011 11:18 am
 

Re: Q8) Manhattan 5lbs : Word Problems

by tommywallach Thu Oct 02, 2014 9:46 am

Hey Xero,

You forgot that the question specifies that he only needs to wash and unload the final load. He doesn't need to reload the next one!

-t