Question

can anyone please answer this question of mine correctly please :(, it's for tomorrow's exam please......... :(​

Answer 1

Answer:

9

Step-by-step explanation:

{ formula of mean :

mean = sum of observations/ no. of observations}

let the three observations are a, b and c.

and we have to calculate c i.e. the third observation.

Now, according to question, mean of first two observations is 6 , that means

(a+b)/2 = 6

a+b = 6(2)

a+b = 12............eq(1)

also, mean of first three observations is 7, so

(a+b+c)/3 = 7

a+b+c = 7(3)

a+b+c = 21...........eq(2)

Now , put the value of a+b from eq(1) in eq(2).

thus, 12+c = 21

c= 21 - 12

c= 9

This is the answer, i.e. the third observation.

Answer 2

Answer:

ans 8 and i lv u

Step-by-step explanation: