149k views
2 votes
Please help.

2 years ago, age of brother was 3 times less than sister's age. this year his age is just 2 times less than his sister's. how old is brother? how old is sister?​

1 Answer

1 vote

Answer:

The sister's age is 8 and the brother's age is 4

Explanation:

Let's make:

x = age of the brother

y = age of the sister

x - 2 = age of the brother two years ago

y - 2 = age of the sister two years ago

Two years ago, the age of the sister was three times greater than the age of the brother:

y - 2 = 3(x - 2)

Now, the relation doubles:

y = 2x

Substituting in the first equation:

2x - 2 = 3(x - 2)

Operating:

2x - 2 = 3x - 6

Subtracting 3x -2:

2x - 3x = 2 - 6 = -4

Solving:

x = 4

y =2x = 8

The sister's age is 8 and the brother's age is 4

User Zeenobit
by
6.5k points