PSLE The airmail rates to two countries are shown. Yen sent a letter weighing 79g to Thailand and a letter weighing 18g to India by airmail. How much did she pay altogether?
Mass |
Thailand |
India |
First 20g |
$0.95 |
$1.60 |
Every additional 10g |
$0.65 |
$0.70 |
Mass of the letter to Thailand excluding the first 20 g
= 79 - 20
= 59 g
Sets of additional 10 g of the letter to Thailand
= 59 ÷ 10
= 5 r 9
Sets of additional 10 g and part thereof the letter to Thailand
= 5 + 1
= 6
Amount that Yen paid for the letter to Thailand
= 0.95 + 6 x 0.65
= 0.95 + 3.90
= $4.85
Amount that Yen paid altogether
= 4.85 + 1.60
= $6.45
Answer(s): $6.45