PSLE The airmail rates to two countries are shown. Barbara sent a letter weighing 86g to Indonesia and a letter weighing 30g to China by airmail. How much did she pay altogether?
Mass |
Indonesia |
China |
First 40g |
$0.55 |
$1.10 |
Every additional 20g |
$0.35 |
$0.35 |
Mass of the letter to Indonesia excluding the first 40 g
= 86 - 40
= 46 g
Sets of additional 20 g of the letter to Indonesia
= 46 ÷ 20
= 2 r 6
Sets of additional 20 g and part thereof the letter to Indonesia
= 2 + 1
= 3
Amount that Barbara paid for the letter to Indonesia
= 0.55 + 3 x 0.35
= 0.55 + 1.05
= $1.60
Amount that Barbara paid altogether
= 1.60 + 1.10
= $2.70
Answer(s): $2.70