PSLE The airmail rates to two countries are shown. Esther sent a letter weighing 63g to Thailand and a letter weighing 18g to Canada by airmail. How much did she pay altogether?
Mass |
Thailand |
Canada |
First 20g |
$0.75 |
$1.40 |
Every additional 10g |
$0.35 |
$0.50 |
Mass of the letter to Thailand excluding the first 20 g
= 63 - 20
= 43 g
Sets of additional 10 g of the letter to Thailand
= 43 ÷ 10
= 4 r 3
Sets of additional 10 g and part thereof the letter to Thailand
= 4 + 1
= 5
Amount that Esther paid for the letter to Thailand
= 0.75 + 5 x 0.35
= 0.75 + 1.75
= $2.50
Amount that Esther paid altogether
= 2.50 + 1.40
= $3.90
Answer(s): $3.90