The average of 3, 15, and my number is 40. What is my number?

the average of 3 and 15 is 9

Step-by-step explanation:

102

Step-by-step explanation:

Let your number be n

The average of 3 ,15 and your number is found by adding the three numbers and dividing by 3

(3+15+n)/3

That is equal to 40

(3+15+n)/3=40

Multiply each side by 3 to get rid of the fraction

(3+15+n)/3 *3 = 40*3

(3+15+n) = 120

Combine like terms

18+n = 120

Subtract 18 from each side

18-18 +n = 120-18

n =102

Your number is 102

answer: you need to organize this better it does not make sense.

step-by-step explanation: ?