Question

find the common difference of the AP✔3✔12✔27✔48

Answer 1

It is neither an AP, nor a GP!

See, for AP, common difference between two successive terms should be constant, but here
12-3≠27-12
a.k.a. 9≠15

For GP, common ratio of two successive terms should be same throughout, but here

12/3 ≠ 27/12

a.k.a 4≠2.25

Answer 2

It is not an ap Because difference bw first two term is 9 and bw 2 and 3 is 15