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

Destination	Letters		Postcards
	Mass	Postage Rate	Per piece
New Zealand, Australia	1st 30 g	$1.30	$0.70
	Every additional 10 g or part thereof	$0.20

How much did Xandra pay for the postage when she sent a letter which weighed 56 g and 9 postcards to New Zealand by airmail?
Remaining mass that Xandra had to pay for the letter as it was more than 30 g
= 56 - 30
= 26 g

Number of sets of additional 10 g of the letter that Xandra had to pay for 
= 26 ÷ 10
= 2 r 6

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

Amount that Xandra had to pay for the sets of additional 10 g of the letter
= 3 x 0.20
= $0.60

Total amount that Xandra had to pay for the letter
= 1.30 + 0.60
= $1.90

Amount that Xandra had to pay for the 9 postcards
= 9 x 0.70
= $6.30

Total amount that Xandra paid
= 1.90 + 6.30
= $8.20

Answer(s): $8.20