Halfway Between 21 and 66

When you ask "What number is halfway between 21 and 66?" we assume you mean the number in the exact middle of the two numbers on a number line, as illustrated below, where X=21 and Y=66.

Halfway Between Line

To find the number halfway between 21 and 66, we use the following formula:

(X + Y)/2 = Halfway Between

When we enter 21 and 66 into our formula, we get:

(21 + 66)/2 = 43.5

Thus, the number halfway between 21 and 66 is 43.5.

To check that our answer is correct, we subtract 21 from 43.5 and subtract 43.5 from 66 and compare the two numbers:

43.5 - 21 = 22.5
66 - 43.5 = 22.5

As you can see, the halfway number is 22.5 higher than 21 and 22.5 lower than 66. Therefore, our halfway between answer of 43.5 above is correct.

Halfway Between
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Halfway Between 21 and 67
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