Question

Tue 05/28
11. Find the common ratio of the sequence.
2, -10,50.-250,
0-5
.

Answer 1

-5

Explanation:

Geometric sequences have common ratios.

You can see if a sequence is geometric by computing:

`\frac{\text{term}}{\text{previous term}}`.

If you get the same result per consecutive pair, then there is a common ratio and the sequence is geometric.

Let's see:

`(-250)/(50)=(50)/(-10)=(-10)/(2)`

So if this equations holds (if all 3 fractions equal the same thing), then is geometric and we have also have computed the common ratio.

The first fraction results in -250/50=-5.

The second fraction results in 50/-10=-5.

The third fraction results in -10/2=-5.

All three fractions are equal and so the equation holds so it is geometric and the common ratio is -5.