Calculate the H.C.F. of 24 and 30
The factors of 24 are 1, 2, 3, 4, 6, 8, 12, and 24.
The factors of 30 are 1, 2, 3, 5, 6, 10, 15, and 30.
The common factors of 24 and 30 are 1, 2, 3, and 6.
Therefore, the highest common factor (H.C.F.) of 24 and 30 is 6.