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:
137 comments Page 4 of 14.
Showry said:
1 decade ago
look this....
Total no of students
S = (age < 8) + (age = 8) + (age > 8)
age < 8 = 20%(S) ====> 20S/100
age = 8 ====> 48
age > 8 ====> (2/3)*48 ====>32
S=20S/100 + 48 +32
S=100
Total no of students
S = (age < 8) + (age = 8) + (age > 8)
age < 8 = 20%(S) ====> 20S/100
age = 8 ====> 48
age > 8 ====> (2/3)*48 ====>32
S=20S/100 + 48 +32
S=100
Rishi said:
1 decade ago
How 2/3 comes in abve 8 year students
Sravanreddypailla said:
1 decade ago
Let total=x
exact 8 years = 48
above 8 years = 2/3*48 = 32
so 48+32= 80
given 20% below 8 years therefore reamaining i.e above n exact=80%
from above 80%=80
that means 20%=20(default as we take percentage in hundredths)
TOTAL OF THE ABOVE =100
exact 8 years = 48
above 8 years = 2/3*48 = 32
so 48+32= 80
given 20% below 8 years therefore reamaining i.e above n exact=80%
from above 80%=80
that means 20%=20(default as we take percentage in hundredths)
TOTAL OF THE ABOVE =100
Rahul said:
1 decade ago
@Ramesh
Below 8 years is 20% not 20 its not work out in all problems.
Below 8 years is 20% not 20 its not work out in all problems.
Ayesha said:
1 decade ago
Ramesh method is very good I liked that.
Romita said:
1 decade ago
Thanks ramesh.
Saifz said:
1 decade ago
20% of students out of 100 % are below 8 years, so remaining is 80% = 48 which they are above 8 years or exact 8 years. lets take 80% of students =48
If 80%=40
then 100%=?
i.e 100*48/80=60
and 2/3 of 60=40
Hence total students in class form eq1 and eq2 60+40=100
If 80%=40
then 100%=?
i.e 100*48/80=60
and 2/3 of 60=40
Hence total students in class form eq1 and eq2 60+40=100
Sonam said:
1 decade ago
I like your method; saifz.
Akanksha said:
1 decade ago
Ramesh method is best.
Chitra said:
1 decade ago
Ramesh you done good job. I reall impressed way of answering. Thanks a lot.
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