Felix was given $125 for his birthday from his grandmother. He plans to put this money toward the purchase of a $250 skateboard. The remainder of the money he plans to earn mowing lawns for the rate of $35 each.

What is the least number of lawns Felix will have to mow in order to have enough to buy the skateboard?
A. 3 lawns
B. 4 lawns
C. 7 lawns
D. 8 lawns

First, we need to figure out how much money Felix still needs to earn after his grandmother's gift. $250 - $125 = $125.

Then we need to figure out how many lawns at $35 each it will take to earn that $125. We can set up an equation to solve for the number of lawns:

$35x = $125

Simplifying:

x = 125/35

x ≈ 3.57

Since we can't mow a fraction of a lawn, we need to round up to the next whole number.

Therefore, Felix will need to mow at least 4 lawns to have enough money to buy the skateboard.

The answer is B. 4 lawns.