PSLE The airmail rates to two countries are shown. Tammy sent a letter weighing 81g to Laos and a letter weighing 42g to Switzerland by airmail. How much did she pay altogether?
Mass |
Laos |
Switzerland |
First 50g |
$0.75 |
$1.80 |
Every additional 25g |
$0.35 |
$0.80 |
Mass of the letter to Laos excluding the first 50 g
= 81 - 50
= 31 g
Sets of additional 25 g of the letter to Laos
= 31 ÷ 25
= 1 r 6
Sets of additional 25 g and part thereof the letter to Laos
= 1 + 1
= 2
Amount that Tammy paid for the letter to Laos
= 0.75 + 2 x 0.35
= 0.75 + 0.70
= $1.45
Amount that Tammy paid altogether
= 1.45 + 1.80
= $3.25
Answer(s): $3.25