In a company, the sales in December were equal to the total sales from

Question

In a company, the sales in December were equal to the total sales from January to May - five months during which the average sale was 50% less than the average annual sale. The average sale during June and July was 20% less than the annual average sale. Which of the following represents the best approximation of the sales during August through November as a percentage of the total annual sales?

A. 30%
B. 35%
C. 40%
D. 45%
E. 50%

A. 30%
B. 35%
C. 40%
D. 45%
E. 50%

Abhishekgmat87 · Answer

Let average annual sales be x
Avg Sales from Jan to May = 0.5x
Total sales from Jan to May = 2.5 x
Sales for December = 2.5 x
Avg Sales for June and July = 0.8 x
Total sales for June and July = 1.6 x
 Sales from Aug to Nov = 12 x - (2.5x+2.5x+1.6x) = 5.4x
Reqd percentage =  \frac{5.4x}{12x} *100  = 45

Option D

GMATist1 · Answer

Let average annual sale = 100 i.e there was a sale of 100 each month

January - May total sale would have been 5*100=500, if it was exactly the annual average
But it was 50% less the annual average sale ==> so absolute sale for Jan to May = 250

December = Jan-May = 250

June- July total sale would have been 2*100, if it was exactly the annual average
But it was 20% less than the average annual sale ==> so absolute sale for Jun-July = 80% of 200 = 160

so absolute sale during Aug- Nov = annual sale - absolute sale of every other month = 1200 - 660 = 540

% of total sale = 540/1200 *100 = 45

Regor60 · Answer

Poorly worded problem.

Average annual sales means sales conducted over one or more YEARS not months.

Average monthly sales during the year is the intended meaning.

Posted from my mobile device

Kinshook · Answer

Given: In a company, the sales in December were equal to the total sales from January to May - five months during which the average sale was 50% less than the average annual sale. The average sale during June and July was 20% less than the annual average sale.

Asked: Which of the following represents the best approximation of the sales during August through November as a percentage of the total annual sales?

Let the annual average sale be x
Total annual sales = 12x

Total sales from January to May - five months during which the average sale was 50% less than the average annual sale = .5x*5 = 2.5x
Total sales in December = 2.5x
The average sale during June and July was 20% less than the annual average sale = .8x
The total sales during June and July was 20% less than the annual average sale = 2*.8x= 1.6x
The total sales from August through November = 12x - 2.5x - 2.5x - 1.6x = 5.4x
The best approximation of the sales during August through November as a percentage of the total annual sales = 5.4x/12x *100% = 45%

IMO D

whatsarc · Answer

Months J F M A M J J A S O N D (Jan to December)

Assume sales in D = 100
Therefore JFMAM = 100 
Average of these 5 months is 20. And this 20 is 50% less than avg annual sales
Hence average annual sale is 40 and total annual sale is 40x12 = 480

JJ has 20% less than average annual sale. Means 32 each

Now

JFMAM + JJ + ASON + D = 480
100 + 64 + x + 100= 480

Hence x = 216

216/480 = 45%

Gemmie · Answer

a: sales from Jan to May
b: sales in Jun + Jul
c: sales from Aug to Nov
d: sales in Dec
S = a + b + c + d

(i) d = a

(ii)  \frac{a}{5} = \frac{1}{2} * \frac{S}{12} = \frac{S}{24}

(iii)  \frac{b}{2} = \frac{4}{5} * \frac{S}{12} = \frac{S}{15}

a + b + c + d = S

=>  \frac{5S}{24} + \frac{5S}{24} + c + \frac{2S}{15} = S

=>  \frac{25S}{120} + \frac{25S}{120} + c + \frac{16S}{120} = S

=>  \frac{66S}{120} + c = S

=>  \frac{11S}{20} + c = S

=>  c = \frac{9S}{20} = \frac{45S}{100}

bumpbot · Answer

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In a company, the sales in December were equal to the total sales from

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