Question

The sum of mother, daughter and an boy's age is 54. The mother's age is 26 more than the sum of the ages of the daughter and the boy. The boy's age is 0.4 of the daughter. Find the daughter's age.

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10
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Answer 1

Answer:

√5+2×7=√49=7

Step-by-step explanation:

√5+2×7=√49=7

Answer 2

Answer:

Daughter's age = 10 years

Step-by-step explanation:

Given data

The sum of ages of mother, daughter and a boy = 54

Mother's age is 26 more than sum of ages of daughter and boy

and boy's age is 0.4 of daughter's age

here we need to find daughter's age  

Let  x, y and z are be the ages of mother, daughter and boy

From given data   x + y + z = 54 _(1)

Mother’s age is 26 more than sum of daughter and boys age  

                            x = y + z + 26 _(2)

And boy’s age is 0.4 of the daughters age  z = 0.4y  

Substitute  z = 0.4 y in (1)  and      

            ⇒     x + y + z = 54

            ⇒     x + y + 0.4y = 54

            ⇒     x + 1.4y = 54

            ⇒     x = 54 - 1.4 y  _(3)

Now substitute  z = 0.4y in (2)

             ⇒  x = y + 0.4 y + 26

             ⇒  x = 1.4y + 26 _(4)

      from (3) and (4)

              54 - 1.4 y = 1.4y + 26

             1.4 y + 1.4y = 54 - 26

                          2.8y = 28

                              y =  10

⇒ Daughter's age = 10 years