Question

6 persons standing in queue with different age group, after two years their average age will be 43 and
seventh person joined with them. Hence the current average age has become 45. Find the age of seventh
person?

Answer 1

Answer:

69 years

Step-by-step explanation:

Given : Average age of 6 people after 2 years = 43

           Current Average age of 7 people = 45

To find : Age of 7th person joined

Average age of n people= sum of ages of all n people / n

Average age after 2 years = 43

Therefore present average age = 43 - 2 = 41

Average age of 6 people = sum of ages of 6 people / 6

41 = sum of ages of 6 people / 6

Sum of ages of 6 people = 246

Let age of seventh person joined be 'x' years

Sum of ages of 7 people = sum of ages of 6 people + age of 7th person

sum of ages of 7 people = 246 + x

Average age of 7 people = sum of ages of 7 people /7

45 = ( 246 + x ) / 7

315 = 246 + x

x = 315 - 246

x = 69

Therefore age of 7th person joined = 69 yrs

Answer 2

Answer:

69

Step-by-step explanation:

6 persons standing in queue with different age group, after two years their average age will be 43 and

seventh person joined with them. Hence the current average age has become 45. Find the age of seventh

person?

6 persons standing in queue with different age group, after two years their average age will be 43 and

Sum of their ages after two years = 43 * 6  = 258 years

Sum of current ages of 6 persons = 258 - (2 * 6) =  246 Years

Seventh Person joins and average age = 45 Years

Sum of Ages of 7 persons = 45 * 7 =  315 Years

Age of 7th person = 315 - 246  =   69

the age of seventh  person = 69 Years