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 3 of 9.
Bhanu said:
1 decade ago
Hai Friends.
Try this method.
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 "85".
Try this method.
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 "85".
(1)
Hagar Samy said:
12 months ago
Average = Weights /number of members.
So,
Weights = Average * number of members.
If the Average increased by 2.5, then:
Weights will increase by (2.5 * 8) = 20.
Increase in weights = 20 kg,
The new person's weight = 65 + 20 = 85 kg.
So,
Weights = Average * number of members.
If the Average increased by 2.5, then:
Weights will increase by (2.5 * 8) = 20.
Increase in weights = 20 kg,
The new person's weight = 65 + 20 = 85 kg.
(8)
Jay said:
1 decade ago
In this case problems you people just recall this formula:
N - R = (+ or -)nx.
N - new items added.
R - removed items.
n - average of the sum.
x - decrease or increase.
Put + when increase.
- for decrease.
Now see:
N - 65 = + 8(2.5).
N = 85.
N - R = (+ or -)nx.
N - new items added.
R - removed items.
n - average of the sum.
x - decrease or increase.
Put + when increase.
- for decrease.
Now see:
N - 65 = + 8(2.5).
N = 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.
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
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.
Fahad Riaz said:
6 years ago
Total weight of 8 persons is 520 (65*8).
Now, a total weight of 7 persons is 455 (520-65),
Now try every option to get 2.5% increase,
(455+85)/8 is equal to 67.5,
The total increase is 2.5 KG (67.5-65),
Ans is 85 KG.
Now, a total weight of 7 persons is 455 (520-65),
Now try every option to get 2.5% increase,
(455+85)/8 is equal to 67.5,
The total increase is 2.5 KG (67.5-65),
Ans is 85 KG.
(1)
Bilawal F said:
1 year ago
Let's suppose Average age = 10
Age of sum of 8 ppl = 8×10 = 80
If age increases by 2.5 then = 12.5×8= 100,
Difference= 100-80 = 20.
New person age plus the difference of the ages of the first 8 ppl = 65+20,
= 85.
Age of sum of 8 ppl = 8×10 = 80
If age increases by 2.5 then = 12.5×8= 100,
Difference= 100-80 = 20.
New person age plus the difference of the ages of the first 8 ppl = 65+20,
= 85.
(12)
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.
Amjad said:
3 months ago
The new average is increased by 2.5, so we can say 8 * 2.5 = 20kg is the newly increased weight.
Such that the old person weight is 65 kg.
We have the newly added person weight, so 65 + 20 = 85 kg.
Such that the old person weight is 65 kg.
We have the newly added person weight, so 65 + 20 = 85 kg.
(1)
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers