Question

The average age of five members of a family is 21 years if the age of the grandfather be included the average increased by 9 years the age of the grandfather is

Answer 1

45 is the answer since the total age of all family members are 105 and then grandfather's age will be 45

Answer 2

Answer:

Average age is 21

so total age is 21*5=105

21+9=30

Now the average age of 6 members is 105+30=135

135/6=22.5

If the GF age included avg Age increased by 9 So,

(21+ 9) *(5+1)

=30*6 =180

Now subtract the new Total age from old, 180-105=75

age of the grandfather is 75

Step-by-step explanation: