The usual price of a marker sold at Shop B and C is $16. During a sale, a discount of 25% is given to every marker sold at Shop B. At Shop C, a discount of 50% is given to the 4th marker for every 4 markers sold. How much cheaper would it be if Yen buys 15 markers from Shop B instead of Shop C?

	Shop B	Shop C
Price of 1 marker	75%  $12	100% $16
Every 4th marker		50% $8

Price of 1 marker from Shop B in percentage
= 100% - 25%
= 75%

Price of 1 marker from Shop B at 25% discount
= 75% x 16
= ⁷⁵₁₀₀ x 16 
= $12

Cost of 15 markers from Shop B
= 15 x 12
= $180

Price of the 4th marker from Shop C in percentage
= 100% - 50%
= 50%

Cost of 4th marker at Shop C
= 50% x 16
= ⁵⁰₁₀₀ x 16 
= $8

Cost of 1 set of 4 markers at Shop C
= 16 x 3 + 8
= $56

Number of sets of 4 for markers at Shop C
= 15 ÷ 4
= 3 r 3

Cost of 3 sets of 4 markers at Shop C
= 3 x 56
= $168

Cost of 3 markers at Shop C
= 3 x 8
= $24

Cost of 15 markers at Shop C
= 168 + 24
= $192

Amount cheaper if Yen buys 15 markers from Shop B instead of Shop C
= 192 - 180
= $12

Answer(s): $12