Question

If the Seven times of seventh term of an arithmetic progression is Eleven times of its 11th term, then the 18th term of the arithmetic progression will be _____

• A. 1
• B. 0
• C. 2
• D. -1

Answer 1

Answer:

B. 0

First term is a and common difference is d

n-th term = a + (n-1)d

Seventh term = a + 6d

Eleventh term = a + 10d

Seven times the seventh term is equal to eleven times the eleventh term

7(a + 6d) = 11(a + 10d)

7a + 42d = 11a + 110d

4a = -68d

a = -17d

18th term = a + 17d

= -17d + 17d

= 0