PSLE The airmail rates to two countries are shown. Jane sent a letter weighing 74g to Thailand and a letter weighing 12g to India by airmail. How much did she pay altogether?
Mass |
Thailand |
India |
First 20g |
$0.75 |
$1.90 |
Every additional 10g |
$0.55 |
$0.85 |
Mass of the letter to Thailand excluding the first 20 g
= 74 - 20
= 54 g
Sets of additional 10 g of the letter to Thailand
= 54 ÷ 10
= 5 r 4
Sets of additional 10 g and part thereof the letter to Thailand
= 5 + 1
= 6
Amount that Jane paid for the letter to Thailand
= 0.75 + 6 x 0.55
= 0.75 + 3.30
= $4.05
Amount that Jane paid altogether
= 4.05 + 1.90
= $5.95
Answer(s): $5.95