Halfway Between 20 and 643

When you ask "What number is halfway between 20 and 643?" we assume you mean the number in the exact middle of the two numbers on a number line, as illustrated below, where X=20 and Y=643.

Halfway Between Line

To find the number halfway between 20 and 643, we use the following formula:

(X + Y)/2 = Halfway Between

When we enter 20 and 643 into our formula, we get:

(20 + 643)/2 = 331.5

Thus, the number halfway between 20 and 643 is 331.5.

To check that our answer is correct, we subtract 20 from 331.5 and subtract 331.5 from 643 and compare the two numbers:

331.5 - 20 = 311.5
643 - 331.5 = 311.5

As you can see, the halfway number is 311.5 higher than 20 and 311.5 lower than 643. Therefore, our halfway between answer of 331.5 above is correct.

Halfway Between
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Halfway Between 20 and 644
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