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Arithmetic sequences Worksheet
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1. Find the 9th term of the arithmetic sequence an=25-6(3n+1)
a9=___
Answer:
2. Find the common difference of this arithmetic sequence: 94, 78, 62, 46, 30, 14…
Common difference = ___ (give your answer in exact decimals)
Answer:
3. Determine the common difference for the sequence: 112, 118, 124, 130, 136.
a. Subtract 6
b. Subtract 8
c. Add 8
d. Add 6
4. What is the common difference for the sequence below.
5, 10, 15, 20
a. 2
b. 5
c. −5
d. 10
5. Find the 19th term of the arithmetic sequence an=19+17(n-4)
a19=___
Answer:
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6. Which of the following sequences is arithmetic?
a. 20, 16, 12, 9, 5
b. 20, 15, 10, 5, 0
c. 6, 3, -1, -2, -6
d. -5, -7, -9, -11, -15
7. Write the first five terms of the arithmetic sequence given a1=1.4, d=3.2
a. 1.4, 4.6, 7.8, 11, 14.2
b. 1.4, 4.6, 7.8, 11, 17.4
c. 4.6, 7.8, 11, 14.2, 17.4
d. 7.8, 11, 14.2, 17.4, 20.6
8. Determine whether the sequence 7∙1+2, 7∙2+2, 7∙3+2, 7∙4+2, 7∙5+2… is arithmetic.
a. Yes
b. No
9. Write the nth term rule for the arithmetic sequence with the given term and common difference.
a1 = 4
d = 8
an =
Answer:
10. Determine the common difference for the sequence: 132, 99, 66, 33, 0
a. Add 33
b. Subtract 33
c. Subtract 9
d. Add 9
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Answer Keys
1. -143
2. -16
3. Add 6
4.
5
5. 274
6. 20, 15, 10, 5, 0
7. 1.4, 4.6, 7.8, 11, 14.2
8. Yes
9. 8n-4 , -4+8n
10. Subtract 33
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Printed: February 14, 2022
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