Question

The sum of four consecutive numbers is 42 what is the smallest number

Answer 1

Let us take a number x
The four consecutive numbers will be
x+1, x+2, x+3

Thus our equation will be
x + x+1 + x+2 + x+3 = 42
4x + 6 = 42
4x = 36
x= 36/4
x= 9

Thus the four numbers are (substitute)
x=9
x+1=9+1=10
x+2=9+2=11
x+3=9+3=12

9,10,11,12

Answer 2

Givens
Let the smallest number = x
The second number = x + 1
The third number = x + 2
The largest number = x + 3

Equation
x + x + 1 + x + 2 + x + 3 = 42    Collect the like terms on the left.

Solution
4x + 6 = 42                                Subtract 6 from both sides.
4x = 42 - 6
4x = 36                                      Divide by 4   
x  = 36/4
x = 9


The smallest number = 9