Need expert help - word problem

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Need expert help - word problem

by voodoo_child » Fri Jul 06, 2012 9:07 am
In the month of November, a company sold 3000 items of model A and 1000 items of model B. Items of model A accounted for 60% of the company's monthly sales while items of model B accounted for 40% of the monthly sales. If the company had sold 1000 items of model A less than it actually did, what percent of the total monthly sales would have been attributed to model A?

48
50
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54
55

OA - B)

The question is from Gmatclub test. I was completely stuck. If 60% of items = Item A = 3000 => total = 5000. Also, if 40% of items = item b; how could # of Item b = 1000? How is this possible?

Stuck stuck stuck...please help
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by tutorphd » Fri Jul 06, 2012 10:40 am
A = price of model A; B = price of model B

3000A = 0.60 total
1000B = 0.40 total

divide the two equations: 3A/B = 3/2 -> A/B = 1/2

Now consider the new situation: sold 2000A and 1000B. The ratio of total price for A and B is related to what percent of the total total they are so form the ratio:

2000A / (1000B) = 2A / B = 1 (using the previous equation A/B = 1/2)

If the ratio of the 2000A and 1000B totals is 1:1, then 2000A is 50% of the total total.
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by Bill@VeritasPrep » Fri Jul 06, 2012 5:36 pm
The trick is in the wording. "Monthly sales" means a dollar amount.
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