Age of 3 people using ratios

Question

_{Angelique and Serena’s ages are in the ratio 5:3. Serena’s and Venus’ ages are in the ratio 6:5. If
Angelique is 25 years older than Venus, calculate the average age of the three girls.}

Answer 1

Let x =  Angelique's age

      y =  Serena's age

      z =  Venus' age

 

Then

  x/y = 5/3,  or 3x = 5y            (1)

  y/z = 6/5,  or 5y = 6z             (2)

 

Angelique is 25 years older than Venus, therefore

  x = z + 25                              (3)

From (1) and (2), obtain

  3x = 6z,  or  x = 2z                (4)

Substitute (4) into (3).

  x = x/2 + 25

  x/2 = 25

  x = 50

 

Therefore

  z = x/2 = 25

  y = (6/5)*z = (6/5)*25 = 30

 

Ages are 50, 30, 25

 

Answer:

Average age = (50+30+25)/3 =  35