# 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:

79 comments Page 1 of 8.
Kumar said:
7 months ago

2.5 = 2 + 1/2 = 5/2

8 × 5/2 = 20,

65 + 20 = 85.

8 × 5/2 = 20,

65 + 20 = 85.

(5)

Ozzalll said:
1 year ago

Simple formula.

Weight Of replcae +- (increase/decrease)* number.

Weight Of replcae +- (increase/decrease)* number.

(7)

Iman said:
1 year ago

@Manoj Kumar.

Thanks for explaining. Your method is very helpful to solve the QA questions.

Thanks for explaining. Your method is very helpful to solve the QA questions.

Abhi said:
2 years ago

@Tinku.

Thanks for your explanation.

Thanks for your explanation.

Bhavya sharma said:
3 years ago

Not able to understand.

Here you poised 20kg to this person's weight but not well 20kg should be added to all persons in one person's weight only 2.5kg should be added.

Am I right.

Here you poised 20kg to this person's weight but not well 20kg should be added to all persons in one person's weight only 2.5kg should be added.

Am I right.

(1)

Hemanjali T said:
3 years ago

Can you guys tell me about what happens if the weight is decreased by 2.5 kg? Please explain.

GAGAn said:
3 years ago

Let the average was 10.

Then the sum of 8 people was 10*8 = 80.

When new person comes ,average was increased by 2.5 so new average is 12.5 the new sum = 12.5 * 8 = 100.

So the difference is of 20.

Now whoever new person he will increase the sum by 20 so new person weight is 65 + 20 =85 is the Answer.

Then the sum of 8 people was 10*8 = 80.

When new person comes ,average was increased by 2.5 so new average is 12.5 the new sum = 12.5 * 8 = 100.

So the difference is of 20.

Now whoever new person he will increase the sum by 20 so new person weight is 65 + 20 =85 is the Answer.

(12)

Chitti said:
4 years ago

By using formula,

a = r+nx ------>

a = Added value.

r = Removed value.

n = Number of persons.

x = Change in avg.

So,

a = 65+8(2.5).

a = 85 is new person weight.

a = r+nx ------>

a = Added value.

r = Removed value.

n = Number of persons.

x = Change in avg.

So,

a = 65+8(2.5).

a = 85 is new person weight.

(7)

Saravanan said:
4 years ago

Let x be an average of 8 persons.

Let y be the weight of the new person.

(x+y-65)/8 = (x/8)+2.5,

x+y-65 = x+20,

y-65 = 20,

y = 85.

Let y be the weight of the new person.

(x+y-65)/8 = (x/8)+2.5,

x+y-65 = x+20,

y-65 = 20,

y = 85.

(2)

Fahad Riaz said:
5 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)

Post your comments here:

Quick links

Quantitative Aptitude

Verbal (English)

Reasoning

Programming

Interview

Placement Papers