The usual price of a stapler sold at Shop A and B is $40. During a sale, a discount of 25% is given to every stapler sold at Shop A. At Shop B, a discount of 40% is given to the 4th stapler for every 4 staplers sold. How much cheaper would it be if Penelope buys 14 staplers from Shop A instead of Shop B?

	Shop A	Shop B
Price of 1 stapler	75%  $30	100% $40
Every 4th stapler		60% $24

Price of 1 stapler from Shop A in percentage
= 100% - 25%
= 75%

Price of 1 stapler from Shop A at 25% discount
= 75% x 40
= ⁷⁵₁₀₀ x 40 
= $30

Cost of 14 staplers from Shop A
= 14 x 30
= $420

Price of the 4th stapler from Shop B in percentage
= 100% - 40%
= 60%

Cost of 4th stapler at Shop B
= 60% x 40
= ⁶⁰₁₀₀ x 40 
= $24

Cost of 1 set of 4 staplers at Shop B
= 40 x 3 + 24
= $144

Number of sets of 4 for staplers at Shop B
= 14 ÷ 4
= 3 r 2

Cost of 3 sets of 4 staplers at Shop B
= 3 x 144
= $432

Cost of 2 staplers at Shop B
= 2 x 24
= $48

Cost of 14 staplers at Shop B
= 432 + 48
= $480

Amount cheaper if Penelope buys 14 staplers from Shop A instead of Shop B
= 480 - 420
= $60

Answer(s): $60