Question

The first term of an arithmetic sequence is 24 and the 19 term is-48. What is the

common difference?

Answer 1

common difference d = - 4

Explanation:

the nth term of an arithmetic sequence is

`a_(n)` = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

given a₁ = 24 and a₁₉ = - 48 , then

24 + 18d = - 48 ( subtract 24 from both sides )

18d = - 72 ( divide both sides by 18 )

d = - 4