Aptitude - Percentage - Discussion

Why 8 years of students = 2/3 of 48? Please explain.

Let a total number of the student be 100% out of which 20% of students are below 8years of age so remaining 80% of students are either 8years of age or above 8years of age.

No of students of 8years age=48(given)


No of students above 8years age=2/3* no of students of 8years age
= 2/3*48,
= 32.

80% of students= no of students of 8years age + no of student above 8years age.
80% of students=48+32,
=80.
(We have to find total students in the school so)

100% of students=80/80*100.
=100.

Total number of students in the school are 100.

@Ramesh.

Your explanation is good and it is easy.

Please slove.

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

80%of x=48+2/3*48.
80/100=48+32,
4/5 x=80,
X=400/4=100.

Best explanation @Ramesh.

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.

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.

2/3(students of 8 years age) = 48.
So number of age of 8 years students is 48*3/2 = 72.
And number of students above 8 years age is 48.

So we can conclude 80% of students of class is 72+48 = 120.
Therefor 100% of students number become 120*100/80 = 150.
So students of below 8 years age is 30.

How to find 20%?