In a Venn diagram, solve the equation below
In an examination, 31 candidates passed chemistry, 29 passed physics and 3 failed both subjects. If 50 candidates sat for the examination, how many of them passed chemistry only
To solve this problem, we can use a Venn diagram. We have the following information:
- 31 candidates passed chemistry
- 29 candidates passed physics
- 3 candidates failed both subjects
- 50 candidates sat for the examination
Let's draw a Venn diagram to represent this information.
First, we draw two circles to represent chemistry and physics.
In the chemistry circle, we write "31" to represent the 31 candidates that passed chemistry.
In the physics circle, we write "29" to represent the 29 candidates that passed physics.
Now, we know that 3 candidates failed both subjects, so we write "3" in the overlapping region of the circles.
To find the number of candidates that passed chemistry only, we need to subtract the number of candidates that passed both chemistry and physics from the total number of candidates that passed chemistry.
The number of candidates that passed both chemistry and physics is 3.
So, the number of candidates that passed chemistry only is 31 - 3 = 28.
Therefore, 28 candidates passed chemistry only.