GCSE Maths - Scaling Up and Down Using Proportions #87

The video tutorial explains how to use proportions to scale quantities up or down. It covers examples such as calculating the cost of a different number of juice bottles, determining earnings for a catwalker based on the number of cats walked, and adjusting recipe ingredients for a different number of cakes. The key idea is to first find the unit cost or quantity and then scale it to the desired amount.

If 7 bottles of juice cost £4.20, how much would 5 bottles cost?

• £4.00

• £2.50

• £3.60

• £3.00

Julia earns £45 for walking 18 cats. How much does she earn per cat?

• £1.50

• £3.00

• £2.50

• £2.00

If Julia walks 34 cats, how much will she earn?

• £90

• £75

• £85

• £80

For a recipe that makes 12 cakes using 180 grams of sugar, how much sugar is needed for one cake?

• 12 grams

• 20 grams

• 15 grams

• 18 grams

If Elsa wants to bake 18 cakes, how much sugar will she need?

• 270 grams

• 240 grams

• 250 grams

• 300 grams