Question

10 cakes cost £3.50. how much do 3 cakes cost?

Answer 1

Solving: Rule of three (directly proportional)
10 cakes → £3.50
3 cakes → y


`(10)/(3) = (3.50)/(y)`
Product of extremes equals product of means:

`10*y = 3.50*3`

`10y = 10.5`

`y = (10.5)/(10)`

`y = 1.05`

Therefore:
3 cakes cost £1.05

Answer 2

So u need to use 3.50/10*3

0.35*3=1.05