The Mean of 6 numbers is 18. If one more number is included, the mean of the 7 numbers will be 20. What is the number that is included?

Correct option is B

Given:
Mean of 6 numbers = 18
Mean of 7 numbers (after including one more number) = 20
Formula Used:
Mean = $$\frac{\text{Sum of numbers}}{\text{Number of terms}}$$​
Solution:
Sum of 6 numbers =$$\text{Mean} \times \text{Number of terms} = 18 \times 6 = 108$$​
Sum of 7 numbers = $$20 \times 7 = 140$$​
Included number = Sum of 7 numbers - Sum of 6 numbers = 140 - 108 = 32