Question

The arithmetic mean of three numbers is 147.If the mean of the first two numbers is 141.What is the third number?



a. 18

Answer 1

Hope it must help you

Answer 2

Answer:

159

Step-by-step explanation:

The arithmetic mean of three numbers is 147.

$Mean = \frac{\text{Sum of all observations}}{\text{No. of observations}}$

$147 = \frac{\text{Sum of 3 numbers}}{3}$

$147 \times 3=\text{Sum of 3 numbers}$

$441=\text{Sum of 3 numbers}$

The mean of the first two numbers is 141.

$141= \frac{\text{Sum of first 2 numbers}}{2}$

$141 \times 2=\text{Sum of first 2 numbers}$

$282=\text{Sum of first 2 numbers}$

So, Third number = Sum of 3 numbers - Sum of first two numbers

                             =441-282

                            = 159

Hence the third number is 159