Question

arithmetic mean of 8,9,10 is?
a) 9
b) 10
c) 11
d)12​

Answer 1

Answer:

$MEAN = \frac{SUM OF OBSERVATIONS }{TOTAL NO OF OBSERVATIONS}$

$= \frac{8+9+10}{3}$

$= \frac{27}{3}$

= (A) 9

Step-by-step explanation:

According to the Question

Let the ratio be 5x : 4x

Total number of people in group = 72

We need to calculate the number of lawyers in the group & it is also given that the ratio of doctor to lawyers is 5:4

Sun of Ratios = Total number of people

Substitute the value we get

:\implies:⟹ 5x + 4x = 72

:\implies:⟹ 9x = 72

:\implies:⟹ x = 72/9

:\implies:⟹ x = 8

Now, putting the value of x = 8

4x = 4×8 = 32