Question

If the mean of x, x + 3, x + 5, x + 7, x + 9 and x + 12 is 12, then the mean of first three  numbers is?​

Answer 1

Step-by-step explanation:

(x+x+3+x+5+x+7+x+9+x+12)/6=12

6x+36=12×6

6x=72-36

x=6

mean. of 3 no s =x+x+3+x+5/3=18+8/3=26/3

Answer 2

Answer:

mean = sum of observations / total number of observations

mean = 12

sum of observations = (x)+(x+3)+(x+5)+(x+7)+(x+9)+(x+12)

=x+x+3+x+5+x+7+x+9+x+12

=6x+36

=6(x+6)

number of observations = 6

12=6(x+6)/6

12=x+6

x=12-6

x=6

first term= x = 6

second term=x+3=6+3= 9

third term=x+5=6+5= 11