Aptitude - Average - Discussion
Discussion Forum : Average - General Questions (Q.No. 12)
12.
The average weight of 16 boys in a class is 50.25 kg and that of the remaining 8 boys is 45.15 kg. Find the average weights of all the boys in the class.
Answer: Option
Explanation:
| Required average |
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| = 48.55 |
Discussion:
31 comments Page 2 of 4.
Sirisha said:
7 years ago
Nice trick, Thanks @Pavan.
Sunita said:
8 years ago
Let's take X=50.25 and Y=45.15.
It's given avg of 16 mem is 50.25 so X= 16*50.25 = 804 and in the same manner 8 member Y= 45.15*8 = 361.2.
The total members are 24 therefore;
AVERAGE = (804+361.2)/24 = 48.55.
It's given avg of 16 mem is 50.25 so X= 16*50.25 = 804 and in the same manner 8 member Y= 45.15*8 = 361.2.
The total members are 24 therefore;
AVERAGE = (804+361.2)/24 = 48.55.
Bala Mayak said:
8 years ago
Superb, nice explanation @Pavan.
Vijay said:
7 years ago
Hi, I am not getting the answer. Can anyone explain me to get it?
Shelly said:
9 years ago
Guys the ratio is divided in 2:1. Now use allegation method.
Farhin Rizvi said:
9 years ago
As given, the average weight of 16 boys in a class = 50.25kg.
Thereby,we can write it as x1 + x2,....x16/16 = 50.25,
= x1 + x2 +.....+ x16 = 50.25 * 16 = 804.
For remaining 8 boys x1 + x2 +....+ x8/8 = 45.15,
= x1 + x2 + x3 + ........ + x8 = 45.15 * 8 = 361.2.
Thereby total number of boys = 16 + 8 = 24.
And total weight = 804 + 361.2 = 1165.2.
Average = 1165.2/24 = 48.55.
Thereby,we can write it as x1 + x2,....x16/16 = 50.25,
= x1 + x2 +.....+ x16 = 50.25 * 16 = 804.
For remaining 8 boys x1 + x2 +....+ x8/8 = 45.15,
= x1 + x2 + x3 + ........ + x8 = 45.15 * 8 = 361.2.
Thereby total number of boys = 16 + 8 = 24.
And total weight = 804 + 361.2 = 1165.2.
Average = 1165.2/24 = 48.55.
KIRAN KUMAR said:
9 years ago
This is a weighted average problem. In weighted average problem the value of the actual weights is not required. The ratio of the weights also will give you the same answer. Thus instead of 8 and 16 we can take the ratios of 8 and 16. i.e. 2 and 1 as our weights.
Vicky said:
9 years ago
Is there any shortcut for this problem?
Bramara said:
9 years ago
Formula for this type of problem is (w1*x1) + (w2*x2) / (w1+w2).
Sms said:
1 decade ago
Very complicated and tough problem. Difficult to solve it and need more explanation.
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