+0

# Arithmetic mean 3 digit number

0
670
3
+107

FInd the arithmetic mean of all 3-digit numbers whose digits are distinct and nonzero

Dec 24, 2018

#1
+1

These are the 3-digit numbers that satisfy the given conditions:
[123, 124, 125, 126, 127, 128, 129, 139, 149, 159, 169, 179, 189, 289, 389, 489, 589, 689, 789]
These are the sums of above 3-digit numbers that satisfy the given conditions:
( 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
These are the "arithmetic means" of the above sums:
(2, 2.333333333, 2.666666667, 3, 3.333333333, 3.666666667, 4, 4.333333333, 4.666666667, 5, 5.333333333, 5.666666667, 6, 6.333333333, 6.666666667, 7, 7.333333333, 7.666666667, 8)

Dec 24, 2018
#2
+107
+1

Thank you. Your answer made perfect sense. I just did not see it. I added all the "arithmetic means and divided by 19 to get 2.16 - was that a next step?

MacTyBoys  Dec 24, 2018
#3
+1

Not really sure what they want! if they want the arithmetic mean of the 19 numbers...123, 124....etc., then all you have do is add them all up and divide the total by 19. I think it comes to: 5100 / 19 =268.42.

Dec 24, 2018