Aptitude - Average - Discussion
Discussion Forum : Average - General Questions (Q.No. 5)
5.
The average weight of 8 person's increases by 2.5 kg when a new person comes in place of one of them weighing 65 kg. What might be the weight of the new person?
Answer: Option
Explanation:
Total weight increased = (8 x 2.5) kg = 20 kg.
Weight of new person = (65 + 20) kg = 85 kg.
Video Explanation: https://youtu.be/ceg2jvHsiJU
Discussion:
84 comments Page 2 of 9.
Jagat said:
1 decade ago
Thank for this simplication.
Shiya said:
1 decade ago
@kumar
Hi kumar in the problem they are saying that it wil be effect 2.5 kg that means may be new person weight will be greater than other remaining 7 persons. In this situation they may be effect rite.
Hi kumar in the problem they are saying that it wil be effect 2.5 kg that means may be new person weight will be greater than other remaining 7 persons. In this situation they may be effect rite.
Radhika said:
1 decade ago
Average of quantities is 22 and average of 36 quantities is 25. What is the average of all the 50 quantities?
Muthu said:
1 decade ago
@Banu nice method.
Chithramol ER said:
1 decade ago
New person weight =Replaced person weight+ (no. Of persons*increased weight).
Replaced person weight =65.
No. Of persons =8.
Increased weight =2.5.
These all values are replaced in the formula, then we get the answer as 85
Replaced person weight =65.
No. Of persons =8.
Increased weight =2.5.
These all values are replaced in the formula, then we get the answer as 85
Ankit saxena said:
1 decade ago
Remember the formula for this type of
new person weight=weight of person tht left+total men*average increased after entry of new men...
Hope it wil help u all
new person weight=weight of person tht left+total men*average increased after entry of new men...
Hope it wil help u all
Rahul said:
1 decade ago
Avg = x.
Sum of 8 person's weight/8 = x.
Sum of 8 person's weight= 8x.
Sum of 8 person's weight = 8x+20.
8x+20-8x-20=0.
8x+20-8x = 20.
Therefore 20+65=85.
Sum of 8 person's weight/8 = x.
Sum of 8 person's weight= 8x.
Sum of 8 person's weight = 8x+20.
8x+20-8x-20=0.
8x+20-8x = 20.
Therefore 20+65=85.
Karthik said:
1 decade ago
(w1+w2+w3+...+w8)/8 = x kg - eq1.
Let w2 be the person who has been replaced.
Let it be denoted by w2n.
So now,
(w1+w2n+w3+....+w8)/8 = x+2.5 - eq2.
Replacing x in eq2 with x from eq1 we get,
w2n-w2 = 20.
=> w2n = 85.
Let w2 be the person who has been replaced.
Let it be denoted by w2n.
So now,
(w1+w2n+w3+....+w8)/8 = x+2.5 - eq2.
Replacing x in eq2 with x from eq1 we get,
w2n-w2 = 20.
=> w2n = 85.
Sandeepkumar said:
1 decade ago
Let x be the average weight,
Total weight incremented is = x+ 2.5.
Then,
avg.
7x-65 = 8(x+2.5).
7x-65 = 8x+20.
Then x = 85.
Total weight incremented is = x+ 2.5.
Then,
avg.
7x-65 = 8(x+2.5).
7x-65 = 8x+20.
Then x = 85.
Amar Sahoo said:
1 decade ago
Let us take 'x' be the new person.
'x' replaces the person having 65 kg weight i.e. x-65.
Total weight increased = (8 x 2.5) kg = 20 kg.
So we can put it in an equation i.e.
x - 65 = 20.
x = 20 + 65.
x = 85 ANS.
'x' replaces the person having 65 kg weight i.e. x-65.
Total weight increased = (8 x 2.5) kg = 20 kg.
So we can put it in an equation i.e.
x - 65 = 20.
x = 20 + 65.
x = 85 ANS.
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