PSLE The airmail rates to two countries are shown. Erika sent a letter weighing 87g to Phillippines and a letter weighing 36g to Australia by airmail. How much did she pay altogether?
Mass |
Phillippines |
Australia |
First 40g |
$0.95 |
$1.80 |
Every additional 20g |
$0.55 |
$0.80 |
Mass of the letter to Phillippines excluding the first 40 g
= 87 - 40
= 47 g
Sets of additional 20 g of the letter to Phillippines
= 47 ÷ 20
= 2 r 7
Sets of additional 20 g and part thereof the letter to Phillippines
= 2 + 1
= 3
Amount that Erika paid for the letter to Phillippines
= 0.95 + 3 x 0.55
= 0.95 + 1.65
= $2.60
Amount that Erika paid altogether
= 2.60 + 1.80
= $4.40
Answer(s): $4.40