Question

The mean of 3 numbers is 4. 2 of the numbers are 1 and 9
What is the third number

Answer 1

2

Explanation:

`\frac{a+b+c}3}= 4\\`

multiply both sides by 3

a+b+c=12

substitute the values we have

1+9+c=12

10+c=12

-10 -10

c=2

so the third number is 2

hope this helped you !