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Bunuel
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The average age of a group of 10 students was 20. The average age incr 13 Mar 2016, 12:47
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C
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15% (low)

Question Stats:

77% (01:10) correct 23% (01:16) wrong based on 139 sessions

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The average age of a group of 10 students was 20. The average age increased by 2 years when two new students joined the group. What is the average age of the two new students who joined the group?

A. 22 years
B. 30 years
C. 32 years
D. 44 years
E. None of these
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C
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The average age of a group of 10 students was 20. The average age incr 13 Mar 2016, 14:06
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let a=average age of 2 new students
200/10=20
(200+2a)/12=22
a=32
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Mathivanan Palraj
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The average age of a group of 10 students was 20. The average age incr 13 Mar 2016, 23:35
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Bunuel
The average age of a group of 10 students was 20. The average age increased by 2 years when two new students joined the group. What is the average age of the two new students who joined the group?

A. 22 years
B. 30 years
C. 32 years
D. 44 years
E. None of these
The total age of 10 students with average 20 = 200
The total age of 12 students with average 22 = 264
The total age of 2 new students = 64
Their average =32
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The average age of a group of 10 students was 20. The average age incr 10 Nov 2016, 03:24
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Bunuel
The average age of a group of 10 students was 20. The average age increased by 2 years when two new students joined the group. What is the average age of the two new students who joined the group?

A. 22 years
B. 30 years
C. 32 years
D. 44 years
E. None of these

it is a weighted average problem


let W1 weight of 10 students and W2 weigh of the new 2 , A1 = 20 , A2 = x and WA = 22

22 = X- (10/2)*2 , thus x = 32
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The average age of a group of 10 students was 20. The average age incr 10 Nov 2016, 10:44
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Bunuel
The average age of a group of 10 students was 20. The average age increased by 2 years when two new students joined the group. What is the average age of the two new students who joined the group?

A. 22 years
B. 30 years
C. 32 years
D. 44 years
E. None of these

Total age of 10 students is 200

Total age of 12 students is 264

Thus total age increases by 64 for 2 students , so average age of the 2 students is 64/2 = 32 years...

Hence, answer will be (C)..
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The average age of a group of 10 students was 20. The average age incr 11 Nov 2016, 08:26
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Bunuel
The average age of a group of 10 students was 20. The average age increased by 2 years when two new students joined the group. What is the average age of the two new students who joined the group?

A. 22 years
B. 30 years
C. 32 years
D. 44 years
E. None of these

We are given that the average age of a group of 10 students was 20. Thus, the sum of the ages of the 10 students is 10 x 20 = 200.

We are also given that the average age increased by 2 years when two new students joined the group. If we let x = the sum of the ages of the two new students, we can use the average formula: average = sum/number to create the following equation:

22 = (200 + x)/12

264 = 200 + x

64 = x

Since the sum of the ages of the two students is 64, the average of those ages is 64/2 = 32.

Answer: C
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The average age of a group of 10 students was 20. The average age incr 09 Dec 2016, 00:43
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Nice Question.
Here is what i did in this Question -->


\(Mean =\frac{Sum}{#}\)

Sum(1)=20*10=> 200
Sum(2)=22*12=> 264

Here the sum of the two students age must be 264-200=64
Hence the average =64/2=32

Hence C
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The average age of a group of 10 students was 20. The average age incr 01 Dec 2020, 01:11
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Hi karishma ,
I'm trying to get hold of distribution approach of mean. Can you help?

As per my understanding
AVG is raised by 2, therefore- New avg 20+2= 22

The sum of ages of the two persons distributes 2 among each member inclusive of them.
12* 2 =24
=> Sum is 24 more than avg
=> 24 +Avg = 24+20 =44
avg age 44/2 =22years

What am I missing with this approach?
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The average age of a group of 10 students was 20. The average age incr 25 Feb 2022, 08:18
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