Answer:
40
Step-by-step explanation:
163, 160,157,... Find the 42nd term
a_1 = 163
common difference d = 160 - 163 = -3
use the formula : a_n = (n - 1)*d + a_1
so
a_42 = (42 - 1)*(-3) + 163
a_42 = 41*(-3) + 163
a_42 = -123 + 163 = 40
