Question

The sum of kimmy and Dora's age is 53.Five years ago, kimmy was 7 years more than half as old as Dora. How old is Dora?

Answer 1

Let the Dora's present age be x

Kimmy's age = 53 – x

5 years ago

Dora's age was = ( x – 5 ) years

Kimmy's age = ( 53 – x – 5 ) years

= ( 48 – x ) yesrs

According to question,

48 – x = 7 + ( x – 5 ) / 2

48 – 7 = x + ( x – 5 ) / 2

41 × 2 = 2x + x – 5

82 = 3x – 5

82 + 5 = 3x

87 = 3x

x = 87 / 3

x = 29

Ans : Dora is 29 years old.

Answer 2

Answer:

40 yrs old

Step-by-step explanation:

let kimmy be = x

and dora = y

x + y = 53

Five years ago means that we will subrtact 5 to their ages

x - 5 + 7 = y/2 - 5

x + 2 = y/2 - 5

Now you can either solve for x or y to substitute to the original equation.

x + 2 = y/2 - 5

x + 2 - 2 = y/2 - 5 - 2

x = y/2 - 7

Subtistute the value of x to the original equation.

x + y = 53

y/2 - 7 + y = 53

2 [y/2 - 7 + y = 53]

y - 14 + 2y = 106

3y - 14 = 106

3y - 14 + 14 = 106 + 14

3y = 120

3y/3 = 120/3

y = 40

then dora is 40

Just to be sure lets solve for Kimmy's age :

x + y = 53

x + 40 = 53

x + 40 - 40 = 53 - 40

x = 13

substitute the 2 values to the 2nd equation :

x + 2 = y/2 - 5

13 + 2 = 40/2 - 5

15 = 20 - 5

15 = 15

so Our answer is correct Dora is 40 years old