hello : the general term is : an = a1+(n-1)×d or : an = ap +(n-p)×d......d is common diffrence let : n=10 and p= 4 a10 = a4 +(10-4)×d 64 = 22 + 6d 6d = 42 d= 7 conclusion : a4 = 22 a3 = 22-7=15 a2=15-7=8 a1= 8-7=1 the first five terms : 1 , 8 , 15 , 22
