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?
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:
135 comments Page 5 of 14.
Rumman said:
1 decade ago
LET TOTAL STUDENT BE X.
THEN STUDENT BELOW AGE 8=20% OF X=20/100 OF X.
STUDENT EXACTLY AT 8 = 48.
STUDENT ABOVE 8 = 2/3 OF 48 = 32.
20X/100+48+32 = X;
20X+4800+3200 = 100X;
80X = 8000;
X = 100;
SIMPLE.
THEN STUDENT BELOW AGE 8=20% OF X=20/100 OF X.
STUDENT EXACTLY AT 8 = 48.
STUDENT ABOVE 8 = 2/3 OF 48 = 32.
20X/100+48+32 = X;
20X+4800+3200 = 100X;
80X = 8000;
X = 100;
SIMPLE.
Nitin said:
9 years ago
20% of student below 8 year. So, 80% of students above and same age.
Number of students of same age = 48.
Number of students of above 8 is 2/3 of 48.
x is total students.
80% of x = 48 + 2/3 of 48.
x = 100.
Number of students of same age = 48.
Number of students of above 8 is 2/3 of 48.
x is total students.
80% of x = 48 + 2/3 of 48.
x = 100.
Prasad M said:
6 years ago
2/3 of 48 -> 32.
32(above 8 years)+48 ( =8 years ) = 80.
From the question rest 20 percent is below 8 years age and is 20 because 80 students already came is assumed to be 80 percent.
: 80+ 20 = 100.
32(above 8 years)+48 ( =8 years ) = 80.
From the question rest 20 percent is below 8 years age and is 20 because 80 students already came is assumed to be 80 percent.
: 80+ 20 = 100.
Agrim dev said:
8 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.
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.
Sankarshan said:
1 decade ago
What ever may be the % of students below 8 years,
Let x be the no of students below 8 years.
So ,
(2/3)x = 48;
x = (48*3)/2;
x = 72;
So total no of students = 72+48 = 120.
Why this answer is wrong?
Let x be the no of students below 8 years.
So ,
(2/3)x = 48;
x = (48*3)/2;
x = 72;
So total no of students = 72+48 = 120.
Why this answer is wrong?
Saif Alam said:
1 decade ago
Let total student = x.
Below 8 year = 20% of x i.e x/5.
Exact 8 year = 48.
Above 8 year = 2/3*48=32.
So,
Total student = x/5 + 48 + 32.
x = x/5 + 80.
x-x/5 = 80.
4x = 400.
x = 100.
Below 8 year = 20% of x i.e x/5.
Exact 8 year = 48.
Above 8 year = 2/3*48=32.
So,
Total student = x/5 + 48 + 32.
x = x/5 + 80.
x-x/5 = 80.
4x = 400.
x = 100.
Vaibhav kumar singh said:
3 years ago
If 20 % = above 8 years so , 80 % = below 8 years + exact 8 years.
therefore 80 % ----> 2/3 of 48=32 (below 8 years) + 48(exact).
80% ---------> 80.
100% ---------> 100.
So, ans = 100.
therefore 80 % ----> 2/3 of 48=32 (below 8 years) + 48(exact).
80% ---------> 80.
100% ---------> 100.
So, ans = 100.
(14)
Gautam said:
10 years ago
No of students of age 8 is 48.
Given no of students above 8 = 2/3 of 48 = 32.
20 % are below 8 age.
Therefore 80 % are equal or above 8.
Therefore 80 % of x = 80 (32 + 42).
So x = 100.
Given no of students above 8 = 2/3 of 48 = 32.
20 % are below 8 age.
Therefore 80 % are equal or above 8.
Therefore 80 % of x = 80 (32 + 42).
So x = 100.
Lily said:
1 year ago
Let,
The no of students = 100
Now, 20% of 100 =20
Above 8 years old are = 48
And 8 years old are :
2/3 of 48
= 32.
Now, the total no of students are: 48 + 32 + 20 = 100.
The no of students = 100
Now, 20% of 100 =20
Above 8 years old are = 48
And 8 years old are :
2/3 of 48
= 32.
Now, the total no of students are: 48 + 32 + 20 = 100.
(57)
Liyakat said:
9 years ago
8 years old students are exact no = 48.
Above 8 years old students are=2/3 * 48 = 32.
8years students+above 8year students = 80.
20% no of below 8 years students = 20/100 * 80 = 96.
Above 8 years old students are=2/3 * 48 = 32.
8years students+above 8year students = 80.
20% no of below 8 years students = 20/100 * 80 = 96.
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