H.C.F of two co-prime numbers is
Any of the numbers
All co-prime numbers have 1 only as their HCF. For example, 3 and 7 are co-prime numbers
The HCF of any two consecutive numbers is 1.
The wheels of a car are of diameter 80 cm each. How many complete revolutions does each wheel make in 10 minutes when the car is travelling at a speed of 66 km per hour