PSLE The airmail rates to two countries are shown. Xuan sent a letter weighing 78g to Malaysia and a letter weighing 31g to Sweden by airmail. How much did she pay altogether?
Mass |
Malaysia |
Sweden |
First 40g |
$0.75 |
$1.20 |
Every additional 20g |
$0.35 |
$0.40 |
Mass of the letter to Malaysia excluding the first 40 g
= 78 - 40
= 38 g
Sets of additional 20 g of the letter to Malaysia
= 38 ÷ 20
= 1 r 18
Sets of additional 20 g and part thereof the letter to Malaysia
= 1 + 1
= 2
Amount that Xuan paid for the letter to Malaysia
= 0.75 + 2 x 0.35
= 0.75 + 0.70
= $1.45
Amount that Xuan paid altogether
= 1.45 + 1.20
= $2.65
Answer(s): $2.65