Aptitude - Percentage - Discussion

Don't use XYZ, it's easier to buy one method i.e.

Below 8 year students = 20%.
And above 8 year students = 48,
And 8 year students = 2/3 of 8 year students,
=> (2/3)*48 => 32.

Simply things if 20% of students below 8 then same and above year students % will be = 100%-20% = 80%,
Then,
80% = 8yr students+8yr above students.
=>80% =48+32.
=>80%=80.
if 80 % students = 80.
Then 1% students =80/80 =1.
Then 100% students =100*1=100.
The total students are 100.

Let the no.of students = x.

Total students = below 8 + exact 8 + above 8.
X = (20/100) + 48 + 2/3(48),
X = 20x/100 + 48 + 32,
X - 20x/100 = 80,
80x/100 = 80,
X = 100.

@Moorthy.

100% - 20% whose age are below 8 = 80%.

Now remaining part is given in that sub part is 48 people are equal to 8 years of age.

And tge people who are in between 8 years I. E in between of equal to 8 and below 8 is 2/3 of 48.

Total = below 8 years + equal to 8 years + more than 8 years = 100.

Let,Total no of students= 100.
20% are below 8,
So, (20/100)*100 = 20,
At 8,
48 members.
Above 8,
2/3 *48 = 32.
Total students = 20 + 48 + 32.
=100.

Thanks, @Sravan!

Exact 8 years = 48.
Above 8 years age=2/3*48=32.
Then, 20% of the students below 8 years, so 80% of the students are 48+32=80.

80---------->80
20---------->?.

80 * 20/80==>1600/80=20.
So, the total number of students is 32+48+20=100.

Below 8 years = 20.
Exact 8 years = 48.
Above 8 years = 2/3*48 = 32.
Now add 48+32+20=100.

80 %x = 48 + 2/3 * 48.

Then why 48 is again added. It's is only said in the question that 2/3 of no of students with the age of 8 years. Can someone explain?

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.

20%.

100-20 = 80% of X.
48*2/3 = 32,
48+32 = 80,
80% of X = 80.
X = 100.