11th Grade Arithmetic and Geometric Sequences Worksheet — Level 1 — Practice Set 2 — Answers
Answer sheet with worked solutions for the 11th Grade sequences & series worksheet.
Success TutoringWorksheetsAnswer sheet11th Grade · Mathematics · Sequences & Series11th Grade Arithmetic and Geometric Sequences Worksheet — Level 1 — Practice Set 2 — Answers
Arithmetic: Tₙ = a + (n − 1)d. Geometric: Tₙ = arn − 1. Show your work.
1.Find the 26th term of the arithmetic sequence 5, 4, 3, 2, …
Answer: −20
- a = 5, d = −1
- T26 = 5 + 25 × −1 = −20
2.Find the 15th term of the arithmetic sequence 15, 16, 17, 18, …
Answer: 29
- a = 15, d = 1
- T15 = 15 + 14 × 1 = 29
3.For the arithmetic sequence 3, 11, 19, 27, …, write the common difference and the rule for the nth term.
Answer: d = 8; Tₙ = 8n − 5
- d = 11 − 3 = 8
- Tₙ = a + (n − 1)d = 3 + (n − 1) × 8 = 8n − 5
4.Find the 11th term of the arithmetic sequence 7, 2, −3, −8, …
Answer: −43
- a = 7, d = −5
- T11 = 7 + 10 × −5 = −43
5.Find the 27th term of the arithmetic sequence 7, 9, 11, 13, …
Answer: 59
- a = 7, d = 2
- T27 = 7 + 26 × 2 = 59
6.Find the 27th term of the arithmetic sequence 5, −1, −7, −13, …
Answer: −151
- a = 5, d = −6
- T27 = 5 + 26 × −6 = −151
7.For the arithmetic sequence 8, 16, 24, 32, …, write the common difference and the rule for the nth term.
Answer: d = 8; Tₙ = 8n
- d = 16 − 8 = 8
- Tₙ = a + (n − 1)d = 8 + (n − 1) × 8 = 8n
8.For the arithmetic sequence 16, 21, 26, 31, …, write the common difference and the rule for the nth term.
Answer: d = 5; Tₙ = 5n + 11
- d = 21 − 16 = 5
- Tₙ = a + (n − 1)d = 16 + (n − 1) × 5 = 5n + 11
9.Find the 22th term of the arithmetic sequence 14, 19, 24, 29, …
Answer: 119
- a = 14, d = 5
- T22 = 14 + 21 × 5 = 119
10.For the arithmetic sequence 19, 26, 33, 40, …, write the common difference and the rule for the nth term.
Answer: d = 7; Tₙ = 7n + 12
- d = 26 − 19 = 7
- Tₙ = a + (n − 1)d = 19 + (n − 1) × 7 = 7n + 12
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