Question

Q.4] The average age of A and B is 12 years, B and C is 9 years and that of C and Dis 23 years. If the
average age of A, B and C is 13 years, find the age of D.​

Answer 1

its the answer

hope it help

Answer 2

SOLUTION

GIVEN

The average age of A and B is 12 years, B and C is 9 years and that of C and Dis 23 years. If the

average age of A, B and C is 13 years

TO DETERMINE

The age of D.

EVALUATION

Here it is given that The average age of A and B is 12 years

∴ Age of A + Age of B = 24 - - - - - (1)

The average age of B and C is 12 years

∴ Age of B + Age of C = 18 - - - - - (2)

The average age of C and D is 23 years

∴ Age of C + Age of D = 46 - - - - - (3)

The average age of A, B and C is 13 years

∴ Age of A + Age of B + Age of C = 39 - - - - (4)

Equation (4) - Equation (1)

Age of C = 15

From Equation (3) we get

15 + Age of D = 46

∴ Age of D = 31

FINAL ANSWER

Age of D = 31 years

━━━━━━━━━━━━━━━━

Learn more from Brainly :-

$1.$ The mean of 5 numbers is 39. If one number is excluded, their mean is 35, find the excluded number

https://brainly.in/question/33419522

2. find the mean proportional to 7/125 and 5/343

https://brainly.in/question/33462350