Grace examines two different size bottles of the same laundry detergent. The price for the 100-ounce bottle is $9.99 and the price for the 150-ounce bottle is $12.99. How much money will Grace save per 100 ounces of she purchased the larger bottle ?

1) $0.01

2) $1.33

3) $2.00

4) $8.66

Solution: 

Choice B is correct.

Price per 100 ounce for the larger bottle can be calculated as

(12.99 * 100) / 150 = 8.66

Therefore, the money Grace will save per 100 ounces, if she purchased the larger bottle

= $9.99 – $8.66 = $1.33