Question

What is the 25th term of this arithmetic sequence? 3,9,15,21,27

Answer 1

75

Explanation:

you need to divide numbers by 3

3×25=75

Answer 2

147

Explanation:

Arithmetic sequence:

a = first term = 3

d = common difference = second term - first term

= 9 - 3

d = 6

n = 25

`\sf \boxed{\bf n^(th) \ term = a + (n-1) d}`

= 3 + (25 - 1)*6

= 3 + 24*6

= 3 + 144

= 147