The usual price of a pencil sold at Shop Q and R is $12. During a sale, a discount of 25% is given to every pencil sold at Shop Q. At Shop R, a discount of 50% is given to the 6th pencil for every 6 pencils sold. How much cheaper would it be if Jade buys 16 pencils from Shop Q instead of Shop R?

	Shop Q	Shop R
Price of 1 pencil	75%  $9	100% $12
Every 6th pencil		50% $6

Price of 1 pencil from Shop Q in percentage
= 100% - 25%
= 75%

Price of 1 pencil from Shop Q at 25% discount
= 75% x 12
= ⁷⁵₁₀₀ x 12 
= $9

Cost of 16 pencils from Shop Q
= 16 x 9
= $144

Price of the 6th pencil from Shop R in percentage
= 100% - 50%
= 50%

Cost of 6th pencil at Shop R
= 50% x 12
= ⁵⁰₁₀₀ x 12 
= $6

Cost of 1 set of 6 pencils at Shop R
= 12 x 5 + 6
= $66

Number of sets of 6 for pencils at Shop R
= 16 ÷ 6
= 2 r 4

Cost of 2 sets of 6 pencils at Shop R
= 2 x 66
= $132

Cost of 4 pencils at Shop R
= 4 x 6
= $24

Cost of 16 pencils at Shop R
= 132 + 24
= $156

Amount cheaper if Jade buys 16 pencils from Shop Q instead of Shop R
= 156 - 144
= $12

Answer(s): $12