PSLE The airmail rates to two countries are shown. Tammy sent a letter weighing 90g to Thailand and a letter weighing 47g to China by airmail. How much did she pay altogether?
Mass |
Thailand |
China |
First 50g |
$0.85 |
$1.90 |
Every additional 25g |
$0.55 |
$0.75 |
Mass of the letter to Thailand excluding the first 50 g
= 90 - 50
= 40 g
Sets of additional 25 g of the letter to Thailand
= 40 ÷ 25
= 1 r 15
Sets of additional 25 g and part thereof the letter to Thailand
= 1 + 1
= 2
Amount that Tammy paid for the letter to Thailand
= 0.85 + 2 x 0.55
= 0.85 + 1.10
= $1.95
Amount that Tammy paid altogether
= 1.95 + 1.90
= $3.85
Answer(s): $3.85