I tell you these facts about a mystery number, c:

* 1.2 < c < 1.3

* c can be written as a fraction with one digit for the numerator and one digit for the denominator.

* Both c and 1/c can be written as finite (non-repeating) decimals.

What is this mystery number?

Guest Apr 2, 2021

#1**0 **

The mystery number is 5/4, and there is no other number satisfying that condition, because:

The denominator must be either 1, 2, 4, 5, or 8, in simplest terms, so that the decimals don't repeat forever, but 1, 2, and 5 cannot work as the denominator, because if you test numbers for the numerator they don't satisfy the condition 1.2

textot Apr 2, 2021