Question

When the outliers are removed, how does the mean change?

dot plot with 1 on 18, 2 on 38, 1 on 40, 3 on 44, 1 on 46, 1 on 48

The mean decreases by 2.75.
The mean increases by 2.75.
The mean increases by 3.25.
There are no outliers.

Answer 1

i know the mean increases

Answer 2

by 3.25

Answer 3

is it?

Answer 4

i think so

Answer 5

@misssunshinexxoxo

Answer 6

I'll check this

Answer 7

thank you

Answer 8

Pretty sure by 3.25; I'll have a friend check @jim_thompson5910

Answer 9

thats what i thought

Answer 10

First , figure out
1 on 18, 2 on 38, 1 on 40, 3 on 44, 1 on 46, 1 on 48
18+2*38+40+3*44+46+48

and then divide by 1+2+1+3+1+1

that is the original mean
then figure out
2*38+40+3*44+46+48
and divide by 2+1+3+1+1
that is the new mean

Answer 11

its 42 and 1/3

Answer 12

witch simplifys to 3.25

Answer 13

What did you get for
18+2*38+40+3*44+46+48
?

Answer 14

360

Answer 15

and what do you get for
1+2+1+3+1+1
?

Answer 16

9

Answer 17

the average is the sum of all the numbers (i.e. 360) divided by the number of numbers (i.e. 9)
so the first mean is 360/9 = what ?

Answer 18

40

Answer 19

now we "toss out the outlier"
which is the number that seems "far away" from the others.
in this case, the 18 seems far away
so now we add up all the numbers 360 take away 18
we get 360-18 = 342
and instead of 9 numbers, we now have 8 numbers.
the new mean is 342/8 = what ?

Answer 20

42.75

Answer 21

so old mean was 40, new mean is 42.75
the new mean is bigger by how much ?

Answer 22

2.75

Answer 23

and that is choice B