Eleven years ago Tina was half as old as Ike will be in 4 years.

This is how I approached it:

m = Ike's age
t = tina's age

The statement says that eleven years ago Tina was half of Ike's age four years from now. If you're having a hard time understanding this, just imagine that eleven years ago Tina was 10 and four years from now Ike is 20. Therefore we know that:

2*(t-11) = m+4
t = (m+4)/2 +11
t = m/2 + 2 + 11
t = m/2 + 13

Easy problem to tackle, guys!

Start by assigning a variable to represent Ike's present age. The problem calls it M.
Next, we want to figure out Ike's age four years from now: M + 4 = Ike's age four years from now.
Ike's age four years from now is twice Tina's age eleven years ago. To put it mathematically, 0.5(M + 4) = Tina's age eleven years ago.
Finally, we need to get back to Tina's present age: 0.5(M + 4) + 11 = Tina's present age.
If we simplify:
Step 1: 0.5(M + 4) + 11 = Tina's present age
Step 2: 0.5M + 2 + 11 = Tina's present age
Step 3: 0.5M + 13 = Tina's present age --> this is B!

Let Ike's present age = m
Therefore, m + 4 = Ike's age in 4 years

Tina's age 11 years ago = 1/2(m + 4)
Tina's present age = 1/2(m + 4 ) + 11

$$=\frac{\left(m+4\right)}{2}+\frac{11}{1}$$
$$\frac{m}{2}+\frac{4}{2}+\frac{11}{1}$$
$$\left(\frac{m}{2}\right)+\left(\frac{2}{1}+\frac{11}{1}\right)$$
$$=\frac{m}{2}+13$$

Answer = B