Halfway Between 9 and 90

When you ask "What number is halfway between 9 and 90?" we assume you mean the number in the exact middle of the two numbers on a number line, as illustrated below, where X=9 and Y=90.

Halfway Between Line

To find the number halfway between 9 and 90, we use the following formula:

(X + Y)/2 = Halfway Between

When we enter 9 and 90 into our formula, we get:

(9 + 90)/2 = 49.5

Thus, the number halfway between 9 and 90 is 49.5.

To check that our answer is correct, we subtract 9 from 49.5 and subtract 49.5 from 90 and compare the two numbers:

49.5 - 9 = 40.5
90 - 49.5 = 40.5

As you can see, the halfway number is 40.5 higher than 9 and 40.5 lower than 90. Therefore, our halfway between answer of 49.5 above is correct.

Halfway Between
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Halfway Between 9 and 91
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