Answer:
12
Step-by-step explanation:
The ratio of cars to trucks to motorcycles is $4:3:2.
If there are $42$ cars and trucks total,
To get how many motorcycles are there
Sum up the ratio of cars and trucks 4:3= 4+3 = 7
Sum up the ratio of cars and trucks and motorcycles
4+3+2 =9
Let the total number of cars and trucks and motorcycles be represented as A
The total number of cars and trucks in the question is 42
(7/9) x A = 42
7A/9 = 42
cross multiply
7A = 42×9 = 378
A= 378/7 = 54
The total number of cars and trucks and motorcycles is 54
To get the number of motorcycles can be calculated through
a. The total number of cars and trucks and motorcycles subtracted by the number of cars and trucks = 54-42=12 or use the ratio which is
2/9 × 54 = 2×6=12