Geometric sequence equations is a grade 9 math skill aligned to Common Core standard HSF.BF.A.2: write arithmetic and geometric sequences both recursively and with an explicit formula, and use them to model situations. Below are 8 practice questions with answers and step-by-step explanations, drawn from the 10 geometric sequence equations problems our math games drill.
The first term of a sequence is 2. Each term after the first is 4 times the preceding term. If an represents the nth term, which equation gives an in terms of n?
Following the pattern: 1st term, or n=1:2⋅40 2nd term, or n=2:2⋅41 3rd term, or n=3:2⋅42 4th term, or n=4:2⋅43 Since each term has an exponent that is 1 less than the term number, the nth term is an=2⋅4n−1.
2
Mid-gameeasy
The first term of a sequence is 8. Each term after the first is 2 times the preceding term. If f(n) represents the nth term, which equation gives f(n) in terms of n?
Following the pattern: 1st term, or n=1:8⋅20 2nd term, or n=2:8⋅21 3rd term, or n=3:8⋅22 4th term, or n=4:8⋅23 Since each term has an exponent that is 1 less than the term number, the nth term is f(n)=8⋅2n−1.
3
Mid-gameeasy
The first term of a sequence is 6. Each term after the first is 3 times the preceding term. If w represents the nth term, which equation gives w in terms of n?
Following the pattern: 1st term, or n=1:6⋅30 2nd term, or n=2:6⋅31 3rd term, or n=3:6⋅32 4th term, or n=4:6⋅33 Since each term has an exponent that is 1 less than the term number, the nth term is w=6⋅3n−1.
4
Mid-gameeasy
The first term of a sequence is 10. Each term after the first is 2 times the preceding term. If an represents the nth term, which equation gives an in terms of n?
Following the pattern: 1st term, or n=1:10⋅20 2nd term, or n=2:10⋅21 3rd term, or n=3:10⋅22 4th term, or n=4:10⋅23 Since each term has an exponent that is 1 less than the term number, the nth term is an=10⋅2n−1.
5
Mid-gameeasy
The first term of a sequence is 4. Each term after the first is 5 times the preceding term. If f(n) represents the nth term, which equation gives f(n) in terms of n?
Following the pattern: 1st term, or n=1:4⋅50 2nd term, or n=2:4⋅51 3rd term, or n=3:4⋅52 4th term, or n=4:4⋅53 Since each term has an exponent that is 1 less than the term number, the nth term is f(n)=4⋅5n−1.
6
Mid-gameeasy
The first term of a sequence is 7. Each term after the first is 2 times the preceding term. If w represents the nth term, which equation gives w in terms of n?
Following the pattern: 1st term, or n=1:7⋅20 2nd term, or n=2:7⋅21 3rd term, or n=3:7⋅22 4th term, or n=4:7⋅23 Since each term has an exponent that is 1 less than the term number, the nth term is w=7⋅2n−1.
7
Mid-gameeasy
The first term of a sequence is 9. Each term after the first is 3 times the preceding term. If an represents the nth term, which equation gives an in terms of n?
Following the pattern: 1st term, or n=1:9⋅30 2nd term, or n=2:9⋅31 3rd term, or n=3:9⋅32 4th term, or n=4:9⋅33 Since each term has an exponent that is 1 less than the term number, the nth term is an=9⋅3n−1.
8
Buzzer beatermedium
The first term of a sequence is 3. Each term after the first is one-half the preceding term. If w represents the nth term, which equation gives w in terms of n?
Following the pattern: 1st term, or n=1:3⋅(21)0 2nd term, or n=2:3⋅(21)1 3rd term, or n=3:3⋅(21)2 4th term, or n=4:3⋅(21)3 Since each term has an exponent that is 1 less than the term number, the nth term is w=3⋅(21)n−1.
Overtime
2 more. Played, not assigned.
The rest of the bank lives inside live head-to-head matches — the placement test finds the right starting difficulty.