Finding the mean and rounding to the nearest tenth?

Question

17,1,24,17
a. 15.3
b. 13.3
c. 20
d. 14.8

72,41,72,95,41
a. 63.7
b. 64.2
c. 64.7
d. 80.3

6,4,9,4,14,9
a. 9.2
b. 8.2
c 7.7
d. 6.2

5,11,14,3,1,12,8,18
a. 10.3
b. 8
c. 23
d. 9

Answer 1

To find the mean, add up all the numbers in the series and divide by the total number of number in there series. For example, the first one is (17+1+24+17)/4

Round to the nearest tenth just means to round your answers you get from working it out to the nearest tenth.

Answer 2

Probably took longer to type up the question than it would have taken to do the calculations in your head.

I do have a way to make it more complicated (a better challenge).

The first one has four items, therefore the sum will be divided by four to find the mean. Instead of adding all numbers, then dividing by four, let us only add up the remainder of each number when divided by 4.

For example, 17 divided by 4 leaves a remainder of 1.
our list becomes 1,1,0,1 (this is called modulo calculation)

The total remainder is 3 which, when divided by 4, will give 0.75; rounded will give 0.8.

Only one answer offers a .8 therefore it could be the solution.
check by adding the integer quotient (4,0,6,4). Yep, it works.

There are even more complicated methods...
What? Oh. You prefer simpler methods?

Sorry.

Answer 3

Add 'em up, divide by the number of items. You can do it!