Geometric Sequences Practice Easy

Find the common ratio for the geometric sequence.

• 10

• 1/2

• 2

• 4

Given the sequence: 125, 25, 5, .... Write the rule a_n using the geometric sequence formula:

• a_n = (125)(1/5)^(n-1)

• a_n = 625(1/5)^(n-1)

• a_n = 625(5)^(n-1)

• a_n = 125 + 5n

What is the 9^th term in a geometric sequence with a common ratio of 2 and a first term of 3?

• 384

• 768

• 1,536

• 27

Is the sequence -432, 72, -12, 2,...geometric?

• yes

• no

Write the explicit formula for the geometric sequence.

• a_n = 4(3)^n-1

• a_n = 3(4)^n-1

• a_n = -4(3)^n-1

• a_n = 3(-4)^n-1

This image shows how a certain bacteria grows in a petri dish. What is the common ratio of this sequence?

• 4

• 3

• 2

• 6

Find a₁₂ in the sequence -1, -3, -9, -27, ...

• -177,147

• -19,683

• -59,049

• 118,098

The rule for finding a_n of a geometric sequence is

a_n = 10(2)^n-1 _{What is the common ratio(r) of the sequence?}

• ²

• ¹⁰

• ²⁰

• 2ⁿ

A geometric sequence has a common ration(r) of 3 and the 8th term (a₈) is 13,122. What is the first term of the sequence (a₁)?

• 3

• 6

• 18

• 2

Daisy received $2 on her first birthday. Each year, the amount of money she received tripled. How much money will she receive on her 5^th birthday?

• $10

• $300

• $162

• $416