jmuduke08 wrote:

I believe I was thinking of an interval formula to determine how many numbers at a certain interval are within a data set. for example, how many intervals of 7 are there in the range 280-3000? thanks again!

First find the first multiple of 7 in the range. 280 is divisible by 7

7*40 = 280

Then find the last multiple in the range. When you divide 3000 by 7, you are left with a remainder of 4. So the last multiple must be 2996.

7*428 = 2996

From 40 to 428, you have 428 - 40 + 1 = 389 multiples of 7 in the given range.

Note: The concept of (3000 - 280)/7 may not always give you the right answer.

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