A bat and a ball together cost $1.10. The bat costs $1.00 more than the ball. How much does the ball cost?
Correct: A
Let's denote the cost of the ball as B. Since the bat costs $1.00 more than the ball, the bat costs B + $1.00. The total cost of both is $1.10, so B + (B + $1.00) = $1.10. Simplifying, 2B + $1.00 = $1.10. Subtract $1.00 from both sides to get 2B = $0.10. Divide both sides by 2 to find B = $0.05.