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 |
$1.70 |
$0.60
|
Every additional 10 g or part thereof |
$0.35 |
How much did Mary pay for the postage when she sent a letter which weighed 65 g and 3 postcards to Indonesia by airmail?
Remaining mass that Mary had to pay for the letter as it was more than 40 g
= 65 - 40
= 25 g
Number of sets of additional 10 g of the letter that Mary had to pay for
= 25 ÷ 10
= 2 r 5
Total number of sets of additional 10 g of the letter that Mary had to pay for
= 2 + 1
= 3
Amount that Mary had to pay for the sets of additional 10 g of the letter
= 3 x 0.35
= $1.05
Total amount that Mary had to pay for the letter
= 1.70 + 1.05
= $2.75
Amount that Mary had to pay for the 3 postcards
= 3 x 0.60
= $1.80
Total amount that Mary paid
= 2.75 + 1.80
= $4.55
Answer(s): $4.55