# 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 1 of 6.

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...

Swetha. said:   10 years ago
This problem can also be done easily in this way:

Average = sum of observations/no.of observations.

Let the sale in 6th month be x.

We have avg = 6500., no.of months = 6.

Then, according to the above formula,

6500 = 6435+6927+6855+7230+6562+x/6.

=>6500*6 = 34009+x.

=>x = 39000-34009.

=>x = 4991. Hence, we got the sale in 6th month as RS. 4991.

Sazid khan said:   6 years ago
This problem can also be done easily in this way:

Average = sum of observations/no.of observations.
Let the sale in a 6th month be x.
We have avg = 6500., no.of months = 6.
Then, according to the above formula,
6500 = 6435+6927+6855+7230+6562+x/6.
=>6500*6 = 34009+x.
=>x = 39000-34009.
=>x = 4991. Hence, we got the sale in 6th month as RS. 4991.

Hi I got the new way but I don't this right or wrong but answer will be coming.

Total 5 month of purchase : (6435+6927+6855+7230+6562) Total = 34009.
You want 6th month sales so divide in total amount 34009 / 6 = 5668.16.

And less six month average amount 6500 - 5668.16 = 831.94.
Coming total multiple in 6 month 831.94 *6 = 4991.64 /-

Shivakumara Y said:   3 years ago
An easy way for this type of problem is;
Here, we have to find 6th month RS?
To find,
Solution:
(Add all 5 month Rs. + 6 th month RS.)/6= 6500,
i.e (34009+ 6th month Rs.)|6 =6500,
34009 + 6th month Rs. = 6500 * 6,
6th month Rs. = 39000 - 34009,
Ans 6th month RS. = 4991.
(2)

Naveen kumar said:   1 decade ago
Hi friends...

Here is the shortcut method to find this problem...

given average sale for 6 months is 6500..

but we don't know 6 month reading...let it be x..

now,according to the formula...

(6435+6927+6855+7230+6562+x) /6 = 6500

34009 + x = 39000

x = 4991.

Sairam.SG said:   2 years ago
Hi friends...

Here is the shortcut method to find this problem.

Given average sale for 6 months is 6500.

But we don't know 6 months reading.

Let it be x.

Now, According to the formula.

(6435+6927+6855+7230+6562+x)/6 = 6500
34009 + x = 39000.
x = 4991.
(42)

Anonymous said:   9 years ago

You can solve aptitude only if you have know concept so try to know concepts and practice more and more examples.

Then everything will be simple. More the examples you practice faster will be calculation after some time.

*****digital root concept****

Sale=6+4+3+5=9.

6+9+2+7=6.
6+8+5+5=6.
7+2+3+0=3.
6+5+6+2=1.

s/n = avg;.

avg = 6+5+0+0 = 2.
(9+6+6+3+1+x)/6 = 2.
9+6+6+3+1+x = 2*6.

7+x = 3.
x = 5(7+5 = 1+2 = 3).

4+9+9+1 = 2+3 = 5.

@avinash
i.e,
since 6500 is d average
we write down all as follows
6435+65=6500
6927-427=6500
6855-355=6500
7230-730=6500
6562-62=6500
add all the values (i.e 65,-427,-355,-730,-62) we get -1509 adding it with 6500 we get 4991