Halfway Between 15 and 66

When you ask "What number is halfway between 15 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=15 and Y=66.

Halfway Between Line

To find the number halfway between 15 and 66, we use the following formula:

(X + Y)/2 = Halfway Between

When we enter 15 and 66 into our formula, we get:

(15 + 66)/2 = 40.5

Thus, the number halfway between 15 and 66 is 40.5.

To check that our answer is correct, we subtract 15 from 40.5 and subtract 40.5 from 66 and compare the two numbers:

40.5 - 15 = 25.5
66 - 40.5 = 25.5

As you can see, the halfway number is 25.5 higher than 15 and 25.5 lower than 66. Therefore, our halfway between answer of 40.5 above is correct.

Halfway Between
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Halfway Between 15 and 67
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