Given that, a11=38 and a16=73
We know that, an=a+(n−1)d
a11=a+(11−1)d
38==a+10d ...(1)
Similarly, a16=a+(16−1)d
73=a+15d ...(2)
On subtracting (1) from (2), we obtain
35 = 5d
d = 7
From equation (1),
38=a+10×(7)
38 - 70 = a
a = -32
a31=a+(31−1)d
=−32+30(7)
=−32+210
=178
Hence, 31st term is 178.