When 12 is added to half the sum of a number and 8 the result is 40. What is the number?

Question

I have to solve it and write an equation.

Answer 1

Let x = the unknown number. When 12 is added to half the sum of a number and 8, the result is 40:

 

(1/2)(x+8) + 12 = 40

 

Subtract 12 from both sides:

 

(1/2)(x+8) = 28

 

Multiply both sides by 2:

 

x+8 = 56

 

Subtract 8 from both sides:

 

x = 48

 

Check:

(1/2)(x + 8) + 12 = 40

(1/2)(48 + 8) + 12 = 40

(1/2)(56) + 12 = 40

28 + 12 = 40

40 = 40

Check!!!