The ratio of family 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 electric cars and the rest were sports cars and saloon cars in the ratio of 5 : 2. If there were 663 more family cars than sports cars, how many saloon cars were there?

Family Cars	Electric Cars	Sports Cars	Saloon Cars	Total Cars
7x7	3x7			10x7
	1x7	2x7		3x7
		5x2	2x2
49 u	7 u	10 u	4 u

The total number of sports cars and saloon cars is the combined repeated identity. Make the total number of sports cars and saloon cars the same. LCM of 2 and 7 is 14.

The total number of electric cars, sports cars and saloon cars is the next combined repeated identity. Make the total number of electric cars, sports cars and saloon cars the same. LCM of 3 and 3 is 21. 

Number of more family cars than sports cars
= 49 u - 10 u
= 39 u

39 u = 663

1 u = 663 ÷ 39 = 17

Number of saloon cars
= 4 u
= 4 x 17
= 68

Answer(s): 68