In a company, in the year 2016, the sales in December were equal to

Question

In a company, in the year 2016, the sales in December were equal to the total sales during January to May. The average monthly sales during June and July was 25% less than the average monthly sales for the year. The average monthly sales during August to November was 20% more than the average monthly sales for the year. What was the ratio of the sales in December to the average monthly sales for the year?

A. 13 : 10
B. 49 : 20
C. 57 : 20
D. 63 : 20
E. 63 : 10

A. 13 : 10
B. 49 : 20
C. 57 : 20
D. 63 : 20
E. 63 : 10

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Adit_ · Answer

Avg sales of year*12 = Total Sales = Dec + Dec + 1.5  + 4*1.2

On simplifying:
Avg. sales of Year*12 = 2Dec + 6.3 
2Dec = 5.7 
Dec/Avg. Sales of Year = 5.7/2 = 57/20.

Answer:  Option C

chloreton · Answer

Assuming values here,

Let avg monthly sales = 100 ; Therefore full year sales = 12*100 =1200

Therefore Avg sales of June and July = 0.75 * Avg monthly sales = 0.75*100 = 75 ; Sum = 75*2 =150

Avg sales of August to November = 1.2 * Avg monthly sales = 1.2*100 = 120 ; Sum = 120*4 = 480

Total - (June and july sales) - (Aug to nov sales) gives me sales of Dec, Jan, Feb, March, April, May.
1200 - 150 - 480 
=570

Since, sales of Dec = Avg sales of Jan to May, we can say dec sales = 570/2 = 285.
Avg sales of Jan to May is also 285

Now the question asks, ratio of Dec sales/Avg monthly sales
=285/100
=57/20

Option C

egmat · Answer

Let's walk you through this step by step.

Let A = average monthly sales for the year. So total annual sales =  12 A.

Now let's convert each piece of information into totals:

1)  Sales in December = D (what we want to find)

2)  December sales = Total sales from January to May. So Jan-May total also equals D.

3)  Average monthly sales for June-July is  25%  less than A =  0.75 A. Since that's the average over  2  months, the total for June + July =  2  ×  0.75 A =  1.5 A.

4)  Average monthly sales for August-November is  20%  more than A =  1.2 A. Since that's the average over  4  months, the total for Aug through Nov =  4  ×  1.2 A =  4.8 A.

Now, the entire year must add up to  12 A:

Jan-May + Jun-Jul + Aug-Nov + December =  12 A

D +  1.5 A +  4.8 A + D =  12 A

2 D +  6.3 A =  12 A

2 D =  5.7 A

D =  5.7 A /  2  =  57 A /  20

So the ratio of December sales to the average monthly sales = D / A =  57  /  20 , which is  57 : 20 .

Answer: C

Key Insight:   Since December sales EQUALS the Jan-May total, you can replace Jan-May with D. That gives you an equation with just one unknown, making it easy to solve.

ExpertsGlobal5 · Answer

C is the correct answer choice.  
 
  Video explanation:

https://www.youtube.com/watch?v=KIybSA5hWAw

In a company, in the year 2016, the sales in December were equal to

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In a company, in the year 2016, the sales in December were equal to

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