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 9 of 14.
Bharathi Jagannadham said:
7 years ago
Under these question, three categories have come i.e,
1. Less than 8 years aged students(A)
2. exact 8 years aged students(C)
3. Greater than 8 years students.(B)
Total no. of students (x) = A+B+C.
We know C=48 no,
From question A= 20%x,
and Remaining B&C=100-20,
=80%.
Then (80/100)x= C+(2/3)C (Where B=(2/3) of C),
(80/100)X= 48+(2/3)48.
By Resolving this X=100 is the answer.
1. Less than 8 years aged students(A)
2. exact 8 years aged students(C)
3. Greater than 8 years students.(B)
Total no. of students (x) = A+B+C.
We know C=48 no,
From question A= 20%x,
and Remaining B&C=100-20,
=80%.
Then (80/100)x= C+(2/3)C (Where B=(2/3) of C),
(80/100)X= 48+(2/3)48.
By Resolving this X=100 is the answer.
Omar Fahad said:
7 years ago
Thanks @Robin Loomba.
Remo said:
7 years ago
Well said, thanks @Priyanka.
Jeevana Sravanthi said:
7 years ago
My answer is 120.
Because, there is no condition like,
No.of students(age>8) = (2/3) * no.of students (age=8).
Its more like:
No.of students(age>8) = no.of students (age=8),
So,
80% of students =(age>8)+(age=8) =48+48=96,
100% of students = 96/0.8 = 120.
Because, there is no condition like,
No.of students(age>8) = (2/3) * no.of students (age=8).
Its more like:
No.of students(age>8) = no.of students (age=8),
So,
80% of students =(age>8)+(age=8) =48+48=96,
100% of students = 96/0.8 = 120.
Siri said:
7 years ago
Thank you @Ramesh.
Puja said:
7 years ago
Let total student =100.
8year below=20,
Now 100-20=80,
8 year= 48,
80-48=32,
Which is equal to 8year above..
Total student= 20 +32+48=100.
8year below=20,
Now 100-20=80,
8 year= 48,
80-48=32,
Which is equal to 8year above..
Total student= 20 +32+48=100.
Parineetha said:
7 years ago
Total number of students = no of students below 8 years+no of students above 8 years. i.e x =48+ 2/3 of 48 = 80.
Vaibhav said:
7 years ago
Thanks @Ramesh.
Aarthi said:
7 years ago
Thank you @Ramesh.
Vennela said:
7 years ago
Why 2/3*48, it should be 2/3*100 right?
Please clear my doubt.
Please clear my doubt.
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