Question

Write down the sum 10 th term of the given sequence 23,21,19,....,5

Answer 1

Answer:

140

Step-by-step explanation:

a = 23, d = -2, n = 10

so,

sum of 10 terms = n/2[2a+(n-1)d]

= 10/2 [2×23 + 9×-2]

= 5 × 28

= 140