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.
Pradeep said:
7 years ago
x students in total,
(100 - 20)% * x = 80% * x.
80/100 * x = 48+(2/3)48,
(80/100)*x=48+32=80,
80% is 80, then 100% of 100.
(100 - 20)% * x = 80% * x.
80/100 * x = 48+(2/3)48,
(80/100)*x=48+32=80,
80% is 80, then 100% of 100.
Nisha said:
7 years ago
Why add 48 in 80% of x = 48 +2/3of 48?
Please explain this step.
Please explain this step.
Soukhya G M said:
7 years ago
Thank you all for explaining this. I get it now.
Mallikarjun Reddy said:
7 years ago
Well said, Thanks @Ramesh.
M.Suresh said:
7 years ago
1/5*X+48+2/3*48 = X.
1/5*X+48+32 = X,
80 = (5X-X)/5,
80*5 = 4X,
400/4 = X,
100 = X.
1/5*X+48+32 = X,
80 = (5X-X)/5,
80*5 = 4X,
400/4 = X,
100 = X.
Vennela said:
7 years ago
Why 2/3*48, it should be 2/3*100 right?
Please clear my doubt.
Please clear my doubt.
Aarthi said:
7 years ago
Thank you @Ramesh.
Vaibhav said:
7 years ago
Thanks @Ramesh.
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.
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.
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