Question

In the observations -2, -9, 31, 28, 41, 13, if we write 9 instead of (-9), then the new mean = ______(a) 20
(b) 17
(c) 13
(d) 22

Answer 1

Answer:

20

Step-by-step explanation:

the observations -2, -9, 31, 28, 41, 13

sum of observations = -2-9+31+28+41+13 = 102

observations = 6

mean = 102/6= 17

if -9 is changed to 9

then 9-(-9)=18 is added in total

and observations = 6

so mean added =18/6 =3

new mean =17+3 = 20

Verification :

the observations -2, 9, 31, 28, 41, 13

sum of the observations -2+9+31+28+41+13 =120

mean =120/6 =20