PSLE The airmail rates to two countries are shown. Zoe sent a letter weighing 57g to Phillippines and a letter weighing 13g to Sweden by airmail. How much did she pay altogether?
Mass |
Phillippines |
Sweden |
First 20g |
$0.55 |
$1.20 |
Every additional 10g |
$0.15 |
$0.50 |
Mass of the letter to Phillippines excluding the first 20 g
= 57 - 20
= 37 g
Sets of additional 10 g of the letter to Phillippines
= 37 ÷ 10
= 3 r 7
Sets of additional 10 g and part thereof the letter to Phillippines
= 3 + 1
= 4
Amount that Zoe paid for the letter to Phillippines
= 0.55 + 4 x 0.15
= 0.55 + 0.60
= $1.15
Amount that Zoe paid altogether
= 1.15 + 1.20
= $2.35
Answer(s): $2.35