The table shows the airmail rates for sending letters and postcards to some countries.
Destination |
Letters |
Postcards |
|
Mass |
Postage Rate |
Per piece |
Korea, Japan
|
1st 30 g |
$1.20 |
$0.50
|
Every additional 10 g or part thereof |
$0.30 |
How much did Kathy pay for the postage when she sent a letter which weighed 102 g and 7 postcards to Korea by airmail?
Remaining mass that Kathy had to pay for the letter as it was more than 30 g
= 102 - 30
= 72 g
Number of sets of additional 10 g of the letter that Kathy had to pay for
= 72 ÷ 10
= 7 r 2
Total number of sets of additional 10 g of the letter that Kathy had to pay for
= 7 + 1
= 8
Amount that Kathy had to pay for the sets of additional 10 g of the letter
= 8 x 0.30
= $2.40
Total amount that Kathy had to pay for the letter
= 1.20 + 2.40
= $3.60
Amount that Kathy had to pay for the 7 postcards
= 7 x 0.50
= $3.50
Total amount that Kathy paid
= 3.60 + 3.50
= $7.10
Answer(s): $7.10