Question 69963
I think what you are asking is, "If 4 times a number is added to 13, the result is 29.  What
is the number?"

You can use x to represent the unknown number and then write this problem in equation form as:

{{{4x + 13 = 29}}}

Subtract 13 from both sides of the equation to eliminate it from the left side of the equation.
The result of this subtraction is:

{{{4x = 29-13 = 16}}}

or just:

{{{4x = 16}}}

Now divide both sides by 4 so that you just have x on the left side:

{{{4x/4 = 16/4}}}

After this division the left side is just x and the right side is 4.  The answer is that the 
missing number is 4.

Check:  Does 29 = 13+(4*4).  It does because 13 + 4*4 = 13 + 16 = 29.

Hope this helps you see your way through this problem.