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.
Chitti said:
9 years ago
The average age of a group of 12 persons is 40 years. If one more person is included then average increases by 1. What is the age of new person?
Anis said:
8 years ago
@Chitti.
Answer : 53 years.
(Sum of age of 12 people)/12= 40 [given].
Thus, Sum of age of 12 people= 480 years.
Let 'x' be the age of the new person.
(Sum of age of 12 people + x)/13 = 41 [given, average increases by 1].
Sum of age of 12 people + x = 533.
480 + x= 533.
x= 53.
Answer : 53 years.
(Sum of age of 12 people)/12= 40 [given].
Thus, Sum of age of 12 people= 480 years.
Let 'x' be the age of the new person.
(Sum of age of 12 people + x)/13 = 41 [given, average increases by 1].
Sum of age of 12 people + x = 533.
480 + x= 533.
x= 53.
Abhishek said:
8 years ago
@Chitti.
Now, pepole is 13.
Avg. inc by 1.
Therefor 40 + 1><13 = 53.
Now, pepole is 13.
Avg. inc by 1.
Therefor 40 + 1><13 = 53.
Riddhi said:
8 years ago
It's said in question that avg increase by 2.5,
So we can say orginal average maybe X.
X+ 2.5 is avg of 8 people when a new person added instead of a man having 65 kg.
So Wat I meant is deviation is 2.5 or difference 2.5 ( avg b4 a new person was not added )---(Avg after a new person got added).
2.5*8 = 20 kg is the weight that is needed to be disturbed amongst 5 people to get avg of 2.5 so,
20+65 = 85kg.
So we can say orginal average maybe X.
X+ 2.5 is avg of 8 people when a new person added instead of a man having 65 kg.
So Wat I meant is deviation is 2.5 or difference 2.5 ( avg b4 a new person was not added )---(Avg after a new person got added).
2.5*8 = 20 kg is the weight that is needed to be disturbed amongst 5 people to get avg of 2.5 so,
20+65 = 85kg.
Marshall said:
8 years ago
The mean mass of 5 men is 78kg, the mass of four of them are 74kg, 76kg, 77kg and 86kg, please what is the mass of the fifth?
Lakshmi said:
8 years ago
The average age of the mother and her six children is 12 years which is reduced by 5 years if the age of the mother is excluded. How old is the mother?
Please explain it with the answer.
Please explain it with the answer.
Saisangeetha said:
9 years ago
@Bhanu.
Your explanation is good.
Your explanation is good.
Abhishek said:
8 years ago
@Marshall.
The mass of 5th person is 77kg.
The mass of 5th person is 77kg.
Abhi said:
8 years ago
Can we simply take 2.5*8 which 20 and add 20 to 65 which is 85?
Likha kamin said:
8 years ago
I can't understand, according to question sum of all person's is 65 kg and one person is just replaced then in such case we should substract from total weight.
Anyone please clear my confusion.
Anyone please clear my confusion.
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