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Which sets of numbers represent geometric sequences? Check all that apply.

2/5,2/10,2/20,2/40...

11/12,8/12,5/12,2/12

25, 19, 13, 7, ...

4, 12, 36, 108, ...

–5, 5, –5, 5, ...

–3, 0, 3, 6, ...

–8, –2,1/2.1/8...

User Fdan
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2 Answers

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the one above me is correct

User Yamiko
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Answer:

2/5,2/10,2/20,2/40...

4, 12, 36, 108, ...

–5, 5, –5, 5, ...

Explanation:

These 3 sets represent a geometric sequence.

A geometric sequence is a series of numbers where each number is obtained by MULTIPLYING the same fixed number to the previous number.

So, in the first sequence: 2/5,2/10,2/20,2/40...

The multiplying factor is 1/2.

In the second sequence: 4, 12, 36, 108, ...

The multiplying factor is 3

In the 3rd sequence: –5, 5, –5, 5, ...

The multiplying factor is -1.

Most of the other sequences are not geometric sequences, but arithmetic sequences (where the next term is obtained by ADDITION).

User TomH
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