# Question #ddb76

Nov 29, 2017

C, 5 cents

#### Explanation:

Let B stand for Bat and b stand for ball

If the total cost for the bat and ball is $1.1, an equation could be: $1.1 = B + b$Since the Bat costs$1 more than the ball, the equation for Bat could be b + 1

Now put that equation into B, so

$1.1 = B + b = \left(1 + b\right) + b = 1 + 2 b$

Solve for b

Subtract 1 on both sides

$1.1 = 1 + 2 b$

Divide both sides by 2
$.1 = 2 b$

$.05 = b$

The ball therefore costs 0.05, which is 5 cents.

Nov 29, 2017

A common puzzler... Not obvious because the prices are inter-related, and not just additive.
[C] 5 cents

#### Explanation:

Bat + Ball = 1.10
Bat = Ball + 1.00 Substitute into the first one:
Ball + 1.00 + Ball = 1.10
2Ball = 0.10
Ball = 0.05 (5 cents)
Then Bat = Ball + 1.00 = 1.05

CHECK:
Bat + Ball = 1.10
1.05 + 0.05 = 1.10 Correct!