If you double the reciprocal of a certain positive number eight times, the result is the cube of the number. What is the number?

the answer is 4 how is it solved?

If you double the reciprocal of a certain positive number eight times, the result is the cube of the number. What is the number?

the answer is 4 how is it solved?

Let’s say the number equals x. The reciprocal would be 1/x. If you double this eight times you get:

2/x

4/x

8/x

16/x

32/x

64/x

128/x

256/x

We know that this equals x^3 so we can set them equal to each other.

256/x=x^3

Now we can multiply by x to get

256=x^4

Now we can take the fourth root of 256.

The fourth root of 256=4

Hope this helps.

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