how much money was spent on illuminating the gym?

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A number of light bulbs were purchased to illuminate a gym. However, only 2/3 of them were needed and 160 leftover light bulbs were returned. If only 60% percent of their cost, or $96, was reimbursed, how much money was spent on illuminating the gym?

A.160
B.320
C.360
D.372
E.384

OA E

Can someone please break down the question into a simple question and then explain step by step

Thanks! :D
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by LoveTheGMAT » Tue Jan 26, 2010 8:32 am
I think it should be B.
If only 2/3 was needed, then 1/3 was returned. If 160 bulbs were returned, then 1/3 x = 160 and then x = 480. Of those 480 bulbs, 160 were returned, and 320 were used.

As for the price, if 60% of P = 96, then P = 160. So the original price of 160 bulbs was $1 each.

If 320 bulbs were used, then the money spent is $320.

Can you explain how you got 384?

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by linkinpark » Tue Jan 26, 2010 9:21 am
LoveTheGMAT wrote:I think it should be B.
If only 2/3 was needed, then 1/3 was returned. If 160 bulbs were returned, then 1/3 x = 160 and then x = 480. Of those 480 bulbs, 160 were returned, and 320 were used.

As for the price, if 60% of P = 96, then P = 160. So the original price of 160 bulbs was $1 each.

If 320 bulbs were used, then the money spent is $320.

Can you explain how you got 384?
from here


1$ / bulb

so 320 = cost of bulbs + non-refund that we lost
i.e. 160-96 = 64$
so total = 384$
530->480->580
when posting a question don't post OA(even masked) before some discussion.

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by bhumika.k.shah » Tue Jan 26, 2010 4:26 pm
so we r adding that non refund bcoz in a way its a cost to the Co-right?

linkinpark wrote:
LoveTheGMAT wrote:I think it should be B.
If only 2/3 was needed, then 1/3 was returned. If 160 bulbs were returned, then 1/3 x = 160 and then x = 480. Of those 480 bulbs, 160 were returned, and 320 were used.

As for the price, if 60% of P = 96, then P = 160. So the original price of 160 bulbs was $1 each.

If 320 bulbs were used, then the money spent is $320.

Can you explain how you got 384?
from here


1$ / bulb

so 320 = cost of bulbs + non-refund that we lost
i.e. 160-96 = 64$
so total = 384$

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by linkinpark » Tue Jan 26, 2010 4:53 pm
bhumika.k.shah wrote:so we r adding that non refund bcoz in a way its a cost to the Co-right?
Exactly
linkinpark wrote:
LoveTheGMAT wrote:I think it should be B.
If only 2/3 was needed, then 1/3 was returned. If 160 bulbs were returned, then 1/3 x = 160 and then x = 480. Of those 480 bulbs, 160 were returned, and 320 were used.

As for the price, if 60% of P = 96, then P = 160. So the original price of 160 bulbs was $1 each.

If 320 bulbs were used, then the money spent is $320.

Can you explain how you got 384?
from here


1$ / bulb

so 320 = cost of bulbs + non-refund that we lost
i.e. 160-96 = 64$
so total = 384$
530->480->580
when posting a question don't post OA(even masked) before some discussion.

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by linkinpark » Tue Jan 26, 2010 4:54 pm
bhumika.k.shah wrote:so we r adding that non refund bcoz in a way its a cost to the Co-right?
Exactly
linkinpark wrote:
LoveTheGMAT wrote:I think it should be B.
If only 2/3 was needed, then 1/3 was returned. If 160 bulbs were returned, then 1/3 x = 160 and then x = 480. Of those 480 bulbs, 160 were returned, and 320 were used.

As for the price, if 60% of P = 96, then P = 160. So the original price of 160 bulbs was $1 each.

If 320 bulbs were used, then the money spent is $320.

Can you explain how you got 384?
from here


1$ / bulb

so 320 = cost of bulbs + non-refund that we lost
i.e. 160-96 = 64$
so total = 384$
530->480->580
when posting a question don't post OA(even masked) before some discussion.

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by sanju09 » Tue Jan 26, 2010 10:51 pm
bhumika.k.shah wrote:A number of light bulbs were purchased to illuminate a gym. However, only 2/3 of them were needed and 160 leftover light bulbs were returned. If only 60% percent of their cost, or $96, was reimbursed, how much money was spent on illuminating the gym?

A.160
B.320
C.360
D.372
E.384

OA E


Can someone please break down the question into a simple question and then explain step by step

Thanks! :D
If 60% percent of the cost of 160 light bulbs = $96, then 100% percent of the cost of 160 light bulbs = $160, or the light bulb cost $1 each (dealing becomes so easy in such cases where we have a unity to work on). Now, 1/3 is 160 so the total initial purchase is 480, 320 were kept that cost $320, $(160 - 96) = $64 is what they bore as loss in the name of illuminating the gym. Total cost spent on illuminating the gym = $(320 + 64) = [spoiler]$384[/spoiler]. [spoiler]E[/spoiler]
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