Cooking for more people
A dal-bhat recipe feeds 4 people. Cook it for 2, 6, 8 or 10 people instead, and see how the rice, dal, water and salt all change by the same ratio.
Core concept
Amounts in a recipe are in direct proportion to the number of people: each amount × (new number of people ÷ 4), so doubling the people doubles everything
Topic: Maths in everyday life
A recipe tells you how much of each thing to use for a certain number of people. Our dal-bhat for 4 people uses 400 g of rice, 200 g of dal, 1200 mL of water and 8 g of salt. To cook for a different number of people, every amount must change by the same ratio: A way to compare two amounts, like 2 cups of rice to 3 cups of water (2 : 3). All key words. The unitary method makes it easy: first find the amount for one person (divide by 4), then multiply by the number of people. For 6 people, rice is 400 ÷ 4 × 6 = 600 g. If you change only the rice and not the water or salt, the food is spoiled: the ratio between the ingredients must stay the same.
What you will learn
- Scale a recipe using the unitary method.
- Explain why every amount must change by the same ratio.
- Recognise direct proportion in everyday life.
Before you start
- Multiply and divide whole numbers.
Materials
- A kitchen scale and a measuring jug (optional)
Equipment
- None
Procedure
- Record the recipe for 4 people.
- Cook for 8 people, and record.
- Cook for 2 people, and record.
How this simulation is simplified
- The recipe for 4: 400 g rice, 200 g dal, 1200 mL water and 8 g salt.
- Amounts are rounded to whole grams and millilitres.