The table shows the airmail rates for sending letters and postcards to some countries.
Destination |
Letters |
Postcards |
|
Mass |
Postage Rate |
Per piece |
Thailand, Vietnam, Myanmar
|
1st 30 g |
$1.50 |
$0.90
|
Every additional 10 g or part thereof |
$0.40 |
How much did Shiyun pay for the postage when she sent a letter which weighed 91 g and 8 postcards to Thailand by airmail?
Remaining mass that Shiyun had to pay for the letter as it was more than 30 g
= 91 - 30
= 61 g
Number of sets of additional 10 g of the letter that Shiyun had to pay for
= 61 ÷ 10
= 6 r 1
Total number of sets of additional 10 g of the letter that Shiyun had to pay for
= 6 + 1
= 7
Amount that Shiyun had to pay for the sets of additional 10 g of the letter
= 7 x 0.40
= $2.80
Total amount that Shiyun had to pay for the letter
= 1.50 + 2.80
= $4.30
Amount that Shiyun had to pay for the 8 postcards
= 8 x 0.90
= $7.20
Total amount that Shiyun paid
= 4.30 + 7.20
= $11.50
Answer(s): $11.50