A class consist of 2/5 freshman,1/4 sophomores, and 1/10 juniors; the rest are seniors. What fraction of class are seniors?
2/5 + 1/4 + 1/10
8/20 + 5/20 + 2/20 = 15/20 = 3/4
4/4 - 3/4 = ?
so would it be 1/4
Yes.
To find the fraction of the class that are seniors, we need to subtract the fractions of freshmen, sophomores, and juniors from 1 (since the rest are seniors).
Let's calculate step by step:
1. The fraction of freshmen in the class is 2/5.
2. The fraction of sophomores in the class is 1/4.
3. The fraction of juniors in the class is 1/10.
Now, let's add these fractions together to find the total fraction of freshmen, sophomores, and juniors in the class:
2/5 + 1/4 + 1/10
To add fractions, we need to find a common denominator. In this case, the least common denominator is 20:
(8/20) + (5/20) + (2/20) = 15/20
This fraction represents the total fraction of freshmen, sophomores, and juniors in the class.
To find the fraction of seniors in the class, we subtract this fraction from 1 (since the rest are seniors):
1 - 15/20
To subtract fractions, we also need a common denominator:
(20/20) - (15/20) = 5/20
So, the fraction of the class that are seniors is 5/20.