Answer:
3240
Step-by-step explanation:
Sum=n/2(2a+(n-1)d)
=80/2(2*1+(80-1)1)
=40(2+79)
=40*81
=3240
6480.
This is an arithmetic series with first term 2, last term 160 and common difference 2.
Sum = n/2 [ a1 + L)
= (80/2)(2 + 160)
= 40 * 162
= 6480.
