3. The answer is either A, B, or C

Question

Find the first, fourth, and tenth terms of the arithmetic sequence described by the given rule.

A(n) = –3 + (n – 1)(–2.2)


C. –2.2, –11.8, –19.8


B. –3, –9.6, –22.8


C. –3, –11.8, –25


D. 0, –6.6, –19.8

Answer 1

You know an AP is of the form A(n) = a + (n-1)d
It cannot be A or D, since they do not start with -3
You can see that the common difference is -2.2, so the 4th term must by -3 + 3(-2.2) = -3-6.6 = -9.6

Looks like B to me.