The table shows the airmail rates for sending letters and postcards to some countries.

Destination	Letters		Postcards
	Mass	Postage Rate	Per piece
Indonesia, Malaysia	1st 40 g	$0.90	$0.40
	Every additional 10 g or part thereof	$0.45

How much did Shannon pay for the postage when she sent a letter which weighed 63 g and 8 postcards to Indonesia by airmail?
Remaining mass that Shannon had to pay for the letter as it was more than 40 g
= 63 - 40
= 23 g

Number of sets of additional 10 g of the letter that Shannon had to pay for 
= 23 ÷ 10
= 2 r 3

Total number of sets of additional 10 g of the letter that Shannon had to pay for 
= 2 + 1
= 3

Amount that Shannon had to pay for the sets of additional 10 g of the letter
= 3 x 0.45
= $1.35

Total amount that Shannon had to pay for the letter
= 0.90 + 1.35
= $2.25

Amount that Shannon had to pay for the 8 postcards
= 8 x 0.40
= $3.20

Total amount that Shannon paid
= 2.25 + 3.20
= $5.45

Answer(s): $5.45