Question

the mean of observation x, 2x+2, 2x+5, 2x+9 is 30. what is the mean of last two observation.

pls answer fast i will mark you as a brainlist

Answer 1

Answer:

Step-by-step explanation:

observations => x, 2x+2, 2x+5 and 2x+9

mean = 30

sum of observations = 7x + 16

30 = 7x+16/2

60 = 7x + 14

7x = 46

x = 46/7

x = 6.57

mean of last 2 observations = 4(6.57)+2+9

                                               = 26.28 + 11

                                               = 37.28

Answer 2

Answer:

Step-by-step explanation:

30= (x + 2x+2 + 2x+5 + 2x+9)÷4

30=7x+16

x=2

Mean of last 2 observations =(2×2+5 +2×2+9)÷2

=22÷2

=11