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Maggies brother is 3 years younger than twice her age. The sum of their ages is 24. How old is Maggie?

2 Answers

3 votes

Let x be the Maggie's age and y be her brother's age.

Then you have two equations:

1. y = 2x -3, and

2. x + y = 24.

So, you need to solve the system of two linear equations in two unknowns

{ y=2x-3 and x+y= 24

Express y from the second equation y = 24 - x and substitute it into the first equation. You will get 24 - x = 2x - 3.

Simplify it step by step:

24 + 3 = 2x + x,

27 = 3x,

x = 27/3 = 9.

Answer: Maggie is 9 years old

Hope this helps!

User Shawn Whinnery
by
8.0k points
4 votes
  • Maggie: x
  • Maggie's brother: 2x - 3

Add them up to equal 24 in an equation.

(x) + (2x - 3) = 24

Combine like terms.

3x - 3 = 24

Add 3 to both sides.

3x = 27

Divide both sides by 3.

x = 9

  • Maggie is 9 years old.
User Fabrizio
by
8.6k points