PSLE The airmail rates to two countries are shown. Wendy sent a letter weighing 68g to Indonesia and a letter weighing 18g to India by airmail. How much did she pay altogether?
Mass |
Indonesia |
India |
First 20g |
$0.85 |
$1.80 |
Every additional 10g |
$0.45 |
$0.70 |
Mass of the letter to Indonesia excluding the first 20 g
= 68 - 20
= 48 g
Sets of additional 10 g of the letter to Indonesia
= 48 ÷ 10
= 4 r 8
Sets of additional 10 g and part thereof the letter to Indonesia
= 4 + 1
= 5
Amount that Wendy paid for the letter to Indonesia
= 0.85 + 5 x 0.45
= 0.85 + 2.25
= $3.10
Amount that Wendy paid altogether
= 3.10 + 1.80
= $4.90
Answer(s): $4.90