PSLE The airmail rates to two countries are shown. Anna sent a letter weighing 68g to Vietnam and a letter weighing 28g to Canada by airmail. How much did she pay altogether?
Mass |
Vietnam |
Canada |
First 30g |
$0.95 |
$1.70 |
Every additional 15g |
$0.55 |
$0.65 |
Mass of the letter to Vietnam excluding the first 30 g
= 68 - 30
= 38 g
Sets of additional 15 g of the letter to Vietnam
= 38 ÷ 15
= 2 r 8
Sets of additional 15 g and part thereof the letter to Vietnam
= 2 + 1
= 3
Amount that Anna paid for the letter to Vietnam
= 0.95 + 3 x 0.55
= 0.95 + 1.65
= $2.60
Amount that Anna paid altogether
= 2.60 + 1.70
= $4.30
Answer(s): $4.30