Question

What is the missing term in this geometric sequence ..., -32, __, -128, ...?

Answer 1

`color(purple)(-64` or `color(violet)(64`

Explanation:

A geometric sequence is a series in which the number succeeding the first number is got by multiplying the previous number with some fixed ratio, this ratio is known as the common ratio

`color(purple)(-32^(xx2),-64^(xx2),-128^(xx2)....`

The common ratio in this sequence is `2`

So,

`-32*2=color(purple)(-64`

And

`color(purple)(-64)*2=-128`

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But, the common ratio can also be `-2` ans the missing number can be `64`

`color(violet)(-32^(xx-22),64^(xx-12),-128^(xx-2)....`

So,

`-32*-2=color(violet)(64`

And

`color(violet)(64)*-2=-128`