PSLE The airmail rates to two countries are shown. Wendy sent a letter weighing 72g to Malaysia and a letter weighing 15g to Switzerland by airmail. How much did she pay altogether?
Mass |
Malaysia |
Switzerland |
First 20g |
$0.75 |
$1.30 |
Every additional 10g |
$0.45 |
$0.45 |
Mass of the letter to Malaysia excluding the first 20 g
= 72 - 20
= 52 g
Sets of additional 10 g of the letter to Malaysia
= 52 ÷ 10
= 5 r 2
Sets of additional 10 g and part thereof the letter to Malaysia
= 5 + 1
= 6
Amount that Wendy paid for the letter to Malaysia
= 0.75 + 6 x 0.45
= 0.75 + 2.70
= $3.45
Amount that Wendy paid altogether
= 3.45 + 1.30
= $4.75
Answer(s): $4.75