So if the ratio of red to blue is 8:3 and there are 15 blue cars then there are 40 red cars. If the ratio of red to white is 2:10 then then there are 200 white cars.
Explanation: 15 divided by 3 is 5. So you multiply 8 by 5 to get 40. 40:15 reduces to 8:3.
With 40 red cars the ratio of 2:10 would be made into 40:200.
