PSLE The airmail rates to two countries are shown. Fiona sent a letter weighing 78g to Vietnam and a letter weighing 38g to Canada by airmail. How much did she pay altogether?
Mass |
Vietnam |
Canada |
First 40g |
$0.65 |
$1.50 |
Every additional 20g |
$0.25 |
$0.45 |
Mass of the letter to Vietnam excluding the first 40 g
= 78 - 40
= 38 g
Sets of additional 20 g of the letter to Vietnam
= 38 ÷ 20
= 1 r 18
Sets of additional 20 g and part thereof the letter to Vietnam
= 1 + 1
= 2
Amount that Fiona paid for the letter to Vietnam
= 0.65 + 2 x 0.25
= 0.65 + 0.50
= $1.15
Amount that Fiona paid altogether
= 1.15 + 1.50
= $2.65
Answer(s): $2.65