(a)[1]
Carpet covering $6$ square metres costs $258$. Work out how much $10$ square metres will cost.
(b)[1]
If $1$ dirham $= \$0.30$, Amin exchanges $\$90$ for dirhams. Calculate how many dirhams he gets.
(c)[2]
Sabah is topping up a tank with water. It takes $20$ minutes to fill the empty tank when the water flows at $2.4$ litres per minute. Calculate how long it will take to fill the empty tank if the water flows at $4$ litres per minute.