Respuesta :

roundadworthy

Answer:

The sum of their ages now is 13

Step-by-step explanation:

Dally's age = x

Dilly's age = x - 7

In 4 years time Dilly will be half Dally’s age, therefore:

Dilly's age plus four equals to half of Dally’s age plus four,

replacing with the values and variables we know:

x - 7 + 4 = (x + 4) /2

x - 3 = (x + 4) /2

2x - 6 = x + 4 (Multiplying by 2 at both sides)

2x - x = 4 + 6 (Like terms)

x = 10 ⇒ x - 7 = 3

The sum of their ages now is 13 (10 + 3)

abidemiokin

The sum of their ages now is 13 years

Let the age of Dilly be "x"

Let the age of Dally be "y"

If Dilly is 7 years younger than Dally, then;

x = y - 7 ....... 1

In 4 years time, their age will be:

Dilly = x+ 4

Dally = y + 4

If in 4 years' time she will be half Dally’s age, then;

x+4 = 1/2(y+4) ............... 2

Substitute equation 1 intp 2 to have:

y-7+4 = 1/2(y+4)

y - 3 = 1/2(y+4)

2y - 6 = y + 4

2y - y = 6 + 4

y = 10

Recall that x = y - 7

x = 10 - 7

x = 3

Sum of their ages will be x + y = 10 + 3 = 13 years

Hence the sum of their ages now is 13 years

Learn more here: https://brainly.com/question/13805464

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