The usual price of a notebook sold at Shop N and P is $40. During a sale, a discount of 20% is given to every notebook sold at Shop N. At Shop P, a discount of 50% is given to the 6th notebook for every 6 notebooks sold. How much cheaper would it be if Tiffany buys 14 notebooks from Shop N instead of Shop P?

	Shop N	Shop P
Price of 1 notebook	80%  $32	100% $40
Every 6th notebook		50% $20

Price of 1 notebook from Shop N in percentage
= 100% - 20%
= 80%

Price of 1 notebook from Shop N at 20% discount
= 80% x 40
= ⁸⁰₁₀₀ x 40 
= $32

Cost of 14 notebooks from Shop N
= 14 x 32
= $448

Price of the 6th notebook from Shop P in percentage
= 100% - 50%
= 50%

Cost of 6th notebook at Shop P
= 50% x 40
= ⁵⁰₁₀₀ x 40 
= $20

Cost of 1 set of 6 notebooks at Shop P
= 40 x 5 + 20
= $220

Number of sets of 6 for notebooks at Shop P
= 14 ÷ 6
= 2 r 2

Cost of 2 sets of 6 notebooks at Shop P
= 2 x 220
= $440

Cost of 2 notebooks at Shop P
= 2 x 20
= $40

Cost of 14 notebooks at Shop P
= 440 + 40
= $480

Amount cheaper if Tiffany buys 14 notebooks from Shop N instead of Shop P
= 480 - 448
= $32

Answer(s): $32