in a certain class of 40 students each student offers at least one of the mathematics and physics.If 22 students offer physics and 21 students offer mathematics,find how many students offer physics only
You mean "each student takes..."
The school offers classes; students take classes.
If x take both, then
22+21-x = 40
Find x, and then 22-x take only physics
To find out how many students offer physics only, we need to subtract the number of students who offer both physics and mathematics from the total number of students who offer physics.
Let's break down the given information:
- Total number of students in the class = 40
- Number of students who offer physics = 22
- Number of students who offer mathematics = 21
Now, let's find the number of students who offer both physics and mathematics. Since each student offers at least one of the subjects, we can subtract the total number of students who offer both subjects from the total number of students who offer physics:
Number of students who offer physics only = Number of students who offer physics - Number of students who offer both physics and mathematics.
To find the number of students who offer both physics and mathematics, we subtract the number of students who offer mathematics from the total number of students who offer physics:
Number of students who offer both physics and mathematics = Number of students who offer physics - Number of students who offer mathematics.
Therefore, number of students who offer physics only = 22 - (22-21) = 22 - 1 = 21.
Hence, 21 students offer physics only.