1. Navja works in a post office.

The table shows the costs of sending parcels by post.
The cost depends on the mass, m grams, of the parcel.

i) Sai sends each of these four parcels by post.

   He pays with a $20 note.

Work out how much change he receives.

$ ................................................. [4]

On 1 April, the cost of sending any parcel increases by 5%. 

iia) Show that the increase in the cost of sending an Extra large parcel is $0.28 .

[1]

 iib) Avani says 

“As the cost of an Extra large parcel increases by $0.28 then the cost of a Large parcel will also increase by $0.28 to $2.48.”  

Explain why Avani is incorrect.

[1]