Ratio - Make Some Chocolate Crispies
To make these chocolate crispies I used:
- 20 g (grams) of chocolate
- 15 g of cornflakes or similar
This made 1 cake only. Recipe Here
Your mathematics task is to:
1) calculate the ratio of chocolate to cornflakes, and then:
2) work out the amount of ingredients to make 21 cakes.
1) We can see that the ratio of chocolate to cornflakes is 20:15
But this can be simplified further. The Greatest Common Factor is 5, so:
For 20 parts chocolate to 15 parts cornflake, divide each side by 5 and we get 4:3
This is the ratio of chocolate to cornflakes.
2) We want to work out how much chocolate and cornflakes we need to make 21 cakes.
The recipe is for 1 cake but we want 21, so multiply both ingredients by (21 cakes / 1 cake), or simply by 21:
- 21 × 20 = 420
- 21 × 15 = 315
So to make our 21 cakes we need:
- 420 g of chocolate
- 315 g of cornflakes
Question: If we only have 400g of chocolate, how many cakes can we make, and what quantity of cornflakes do we need?