The usual price of a marker sold at Shop S and T is $40. During a sale, a discount of 20% is given to every marker sold at Shop S. At Shop T, a discount of 40% is given to the 5th marker for every 5 markers sold. How much cheaper would it be if Gillian buys 12 markers from Shop S instead of Shop T?

	Shop S	Shop T
Price of 1 marker	80%  $32	100% $40
Every 5th marker		60% $24

Price of 1 marker from Shop S in percentage
= 100% - 20%
= 80%

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

Cost of 12 markers from Shop S
= 12 x 32
= $384

Price of the 5th marker from Shop T in percentage
= 100% - 40%
= 60%

Cost of 5th marker at Shop T
= 60% x 40
= ⁶⁰₁₀₀ x 40 
= $24

Cost of 1 set of 5 markers at Shop T
= 40 x 4 + 24
= $184

Number of sets of 5 for markers at Shop T
= 12 ÷ 5
= 2 r 2

Cost of 2 sets of 5 markers at Shop T
= 2 x 184
= $368

Cost of 2 markers at Shop T
= 2 x 24
= $48

Cost of 12 markers at Shop T
= 368 + 48
= $416

Amount cheaper if Gillian buys 12 markers from Shop S instead of Shop T
= 416 - 384
= $32

Answer(s): $32