# Aptitude - Average - Discussion

Discussion Forum : Average - General Questions (Q.No. 3)
3.
A grocer has a sale of Rs. 6435, Rs. 6927, Rs. 6855, Rs. 7230 and Rs. 6562 for 5 consecutive months. How much sale must he have in the sixth month so that he gets an average sale of Rs. 6500?
Rs. 4991
Rs. 5991
Rs. 6001
Rs. 6991
Explanation:

Total sale for 5 months = Rs. (6435 + 6927 + 6855 + 7230 + 6562) = Rs. 34009.

Required sale = Rs. [ (6500 x 6) - 34009 ]

= Rs. (39000 - 34009)

= Rs. 4991.

Video Explanation: https://youtu.be/tP4hszReksU

Discussion:
59 comments Page 6 of 6.

Why do we multiply 6 with 6500.

6435+6927+6855+7230+6562= 34009
6500*7 =39000
39000-34009 =4991

Gautam Sharma said:   1 decade ago
At First, Multiply 6500x6=39000 (bcoz avg is asking in Q)

Then, add all the 5 sale i.e 34009,

Deduct 39000 from the total sale i.e.34009, it becomes 4991.

Avg=(6435+6927+6855+7230+6565+x)/6=6500
=(34012+x)=6*6500
x=39000-34012=4988 from this can select nearest ans...

Mr. Avinash are you sure 6500-799=4991.

Ya you are exact avinash.

Even all t prblms should be solved by this method.

By considering t nearby value.

Easy method for this is

Assume a nearest number in given number as average

Suppose 6500 as average
and then write down all as follows
6435+65=6500
6927-427=6500
6855-355=6500
7230-730=6500
6562-62=6500
the last number as y+x=6500
the effective should be zero if 6500 is correct average
+65-427-355-730-62+x=0
x=799
to get effective zero we should have the number is -799
therefore the required number is as follows...
4991(6500-799).
explanation is long but it is less time taken...