Answer:
10
Explanation:
Front gear = 2
Rear gear = 5
The number of possible combination of gears :
2 different gears :
We find the number of ways of selecting 1 front gear from 2 and also 1 rear gear from 5
2C1 * 5C1
nCr = n! ÷ (n-r)!r!
2C1 = 2 ÷ 1 = 2
5C1
5C1 = 5! ÷ (5-4)! * 1
5C1 = 5 ÷ 1 = 5
2C1 * 5C1
2 * 5 = 10