PSLE The airmail rates to two countries are shown. Xandra sent a letter weighing 84g to Laos and a letter weighing 29g to Switzerland by airmail. How much did she pay altogether?
Mass |
Laos |
Switzerland |
First 30g |
$0.75 |
$1.40 |
Every additional 15g |
$0.45 |
$0.50 |
Mass of the letter to Laos excluding the first 30 g
= 84 - 30
= 54 g
Sets of additional 15 g of the letter to Laos
= 54 ÷ 15
= 3 r 9
Sets of additional 15 g and part thereof the letter to Laos
= 3 + 1
= 4
Amount that Xandra paid for the letter to Laos
= 0.75 + 4 x 0.45
= 0.75 + 1.80
= $2.55
Amount that Xandra paid altogether
= 2.55 + 1.40
= $3.95
Answer(s): $3.95