### Home > CCA2 > Chapter 6 > Lesson 6.2.2 > Problem 6-122

6-122.

Eniki has a sequence of numbers given by the formula *t*(*n*) = 4(5* ^{n}*).

What are the first three terms of Eniki's sequence?

Substitute

*n*= 1, 2, and 3 into the formula.Chelita thinks the number 312,500 is a term in Eniki's sequence. Is she correct? Justify your answer by either giving the term number or explaining why it is not in the sequence.

Let

*t*(*n*) = 312,500 and solve for*n*. Be sure to divide both sides of the equation by 4 before taking the log of both sides.What kinds of numbers will tell you if it is in the sequence?

Elisa thinks the number 94,500 is a term in Eniki's sequence. Is she correct? Explain.

See part (b).