The arithmetic sequence 2, 6, 10, … 90. The number of terms in the sequence is .....

Answer 1

a = 2, d = 4
term(n) = a + (n-1)d

2 + (n-1)(4) = 90
4(n-1) = 88 , divide each side by 4
n-1 = 22
n = 23

you have 23 terms