The ratio of electric cars to the total number of cars on display in Ken's car shop was 7 : 10. ¹₃ of the remaining cars on display were saloon cars and the rest were family cars and sports cars in the ratio of 2 : 1. If there were 221 more electric cars than family cars, how many sports cars were there?

Electric Cars	Saloon Cars	Family Cars	Sports Cars	Total Cars
7x3	3x3			10x3
	1x3	2x3		3x3
		2x2	1x2
21 u	3 u	4 u	2 u

The total number of family cars and sports cars is the combined repeated identity. Make the total number of family cars and sports cars the same. LCM of 2 and 3 is 6.

The total number of saloon cars, family cars and sports cars is the next combined repeated identity. Make the total number of saloon cars, family cars and sports cars the same. LCM of 3 and 3 is 9. 

Number of more electric cars than family cars
= 21 u - 4 u
= 17 u

17 u = 221

1 u = 221 ÷ 17 = 13

Number of sports cars
= 2 u
= 2 x 13
= 26

Answer(s): 26