The ratio of sports cars to the total number of cars on display in Ken's car shop was 3 : 10. ⁴₇ of the remaining cars on display were family cars and the rest were saloon cars and electric cars in the ratio of 5 : 3. If there were 45 more sports cars than saloon cars, how many electric cars were there?

Sports Cars	Family Cars	Saloon Cars	Electric Cars	Total Cars
3x8	7x8			10x8
	4x8	3x8		7x8
		5x3	3x3
24 u	32 u	15 u	9 u

The total number of saloon cars and electric cars is the combined repeated identity. Make the total number of saloon cars and electric cars the same. LCM of 3 and 8 is 24.

The total number of family cars, saloon cars and electric cars is the next combined repeated identity. Make the total number of family cars, saloon cars and electric cars the same. LCM of 7 and 7 is 56. 

Number of more sports cars than saloon cars
= 24 u - 15 u
= 9 u

9 u = 45

1 u = 45 ÷ 9 = 5

Number of electric cars
= 9 u
= 9 x 5
= 45

Answer(s): 45