for what value of P are (2P-1),7 and 3Pare three consecuctive term of an AP?

to be an AP

7 - (2P-1) = 3P - 7
7-2p+1 = 3p-7
-5p=-15
p=3

check:

2p-1 = 5

AP is 5 , 7 , 9
YUP!