I'll give you some help on the first problem. The sequence is arithmetic so let's suppose that the first of your three terms id k and the common difference is d. The three terms are then
k, k + d and k + 2d
Hence the sum of the three terms, which is 24, is given by
k + k + d + k + 2d = 24 thus
3k + 3d = 24, so
k + d = 8 or d = 8 - k
The product of the three terms is 440 so
k(k + d)(k + 2d) = 440
Substitute d = 8 - k and solve for k.
Use the same technique for the second problem but using the fact that the sequence is geometric not arithmetic.