PSLE The airmail rates to two countries are shown. Usha sent a letter weighing 62g to Phillippines and a letter weighing 14g to Switzerland by airmail. How much did she pay altogether?
Mass |
Phillippines |
Switzerland |
First 20g |
$0.85 |
$1.90 |
Every additional 10g |
$0.55 |
$0.75 |
Mass of the letter to Phillippines excluding the first 20 g
= 62 - 20
= 42 g
Sets of additional 10 g of the letter to Phillippines
= 42 ÷ 10
= 4 r 2
Sets of additional 10 g and part thereof the letter to Phillippines
= 4 + 1
= 5
Amount that Usha paid for the letter to Phillippines
= 0.85 + 5 x 0.55
= 0.85 + 2.75
= $3.60
Amount that Usha paid altogether
= 3.60 + 1.90
= $5.50
Answer(s): $5.50