PSLE The airmail rates to two countries are shown. Jean sent a letter weighing 71g to Vietnam and a letter weighing 36g to Canada by airmail. How much did she pay altogether?
Mass |
Vietnam |
Canada |
First 40g |
$0.95 |
$1.10 |
Every additional 20g |
$0.75 |
$0.35 |
Mass of the letter to Vietnam excluding the first 40 g
= 71 - 40
= 31 g
Sets of additional 20 g of the letter to Vietnam
= 31 ÷ 20
= 1 r 11
Sets of additional 20 g and part thereof the letter to Vietnam
= 1 + 1
= 2
Amount that Jean paid for the letter to Vietnam
= 0.95 + 2 x 0.75
= 0.95 + 1.50
= $2.45
Amount that Jean paid altogether
= 2.45 + 1.10
= $3.55
Answer(s): $3.55