Aptitude - Percentage - Discussion

Discussion Forum : Percentage - General Questions (Q.No. 7)
7.

In a certain school, 20% of students are below 8 years of age. The number of students above 8 years of age is of the number of students of 8 years of age which is 48. What is the total number of students in the school?

72
80
120
150
100
Answer: Option
Explanation:

Let the number of students be x. Then,

Number of students above 8 years of age = (100 - 20)% of x = 80% of x.

80% of x = 48 + 2 of 48
3

80 x = 80
100

x = 100.

Video Explanation: https://youtu.be/yPfocU6DA2M

Discussion:
142 comments Page 11 of 15.

Ashish Kumar Biswas said:   9 years ago
Let,
Total number of student = x.
Given as,
8 years age = 48
8 years above age = 48 *(2/3)
= 32.

Below 8 years age = x*20%

By condition,
X*20%+32+48 = x
Or, x*(20÷100) +80 = x
Or, x - x/5 =80
Or, (5x-x)/5 = 80
Or,4x/5 = 80
Or, x = (80*5)/4
Or, x = 100
So, total number of student = 100.

Ans: 100.

Agrim dev said:   9 years ago
Students who ages are 8 =48,
Students whose ages are above 8=2/3 of 48=32,
Students whose ages are below 8=20%=20(default as percentage is measured on 100)
Therefore total students=48+32+20=100.
Ans:100.

Kundan said:   9 years ago
Best explanation @Ramesh.

Bisikesan behera said:   9 years ago
80%of x=48+2/3*48.
80/100=48+32,
4/5 x=80,
X=400/4=100.

Praveen said:   9 years ago
Please slove.

40%of a number is more the 20% of 650 by 190 find the number with explanation.

Vasu said:   9 years ago
@Ramesh.

Your explanation is good and it is easy.

Mahi said:   9 years ago
Why 8 years of students = 2/3 of 48? Please explain.

NEEVE said:   9 years ago
Thank you @Ramesh.

Gavi said:   8 years ago
Thanks for explaining the solutions.

Bablu said:   8 years ago
Well said @Showry.


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