Question

1.4. Calculate the following

1.4.2. How much will 12 litre juice cost if 1.5 litre costs R24? (3)

1.4.3. Pam poured R240 petrol at a price of R15/litre. How many litres did she pour

Answer 1

1.4.2. Let $x=$ the cost of 12 litre juice. We have a proportion

$$\dfrac{x}{12}=\dfrac{R24}{1.5}$$

$$x=\dfrac{12}{1.5}\cdot R24$$

$$x=R192$$

12 litre juice costs R192.

1.4.3. Let $x=$ the number of litres she poured. Use the ratio

$$x=\dfrac{R240}{R15/litre}=16\ litres$$

Pam poured 16 litres of petrol.