PSLE The airmail rates to two countries are shown. Anna sent a letter weighing 54g to Vietnam and a letter weighing 13g to Canada by airmail. How much did she pay altogether?
Mass |
Vietnam |
Canada |
First 20g |
$0.75 |
$1.50 |
Every additional 10g |
$0.55 |
$0.65 |
Mass of the letter to Vietnam excluding the first 20 g
= 54 - 20
= 34 g
Sets of additional 10 g of the letter to Vietnam
= 34 ÷ 10
= 3 r 4
Sets of additional 10 g and part thereof the letter to Vietnam
= 3 + 1
= 4
Amount that Anna paid for the letter to Vietnam
= 0.75 + 4 x 0.55
= 0.75 + 2.20
= $2.95
Amount that Anna paid altogether
= 2.95 + 1.50
= $4.45
Answer(s): $4.45