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Ali’s age plus her dads age is 50. In 8 years Ali’s dad will be twice as old as she is. Find their ages now

User Bigbearzhu
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1 Answer

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Answer:

Ali is 14 years old.

Ali's dad is 36 years old.

Explanation:

We can find Ali and her dad's ages using a system of equations, where:

  • A represents Ali's current age,
  • and D represents her dad's current age.

----------------------------------------------------------------------------------------------------------First equation:

Since the sum of Ali and her dad's ages is 50, our first equation is given by:

A + D = 50

Second equation:

Since Ali's dad will be twice as old her in 8 years, our second equation is given by:

2(A + 8) = D + 8

Method to solve: Substitution:

First, let's isolate A in the first equation:

(A + D = 50) - D

A = -D + 50

Solving for D:

Now, we can solve for D by substituting -D + 50 for A in the second equation in our system:

2(-D + 50 + 8) = D + 8

2(-D + 58) = D + 8

(-2D + 116 = D + 8) - 8

(-2D + 108 = D) + 2D

(108 = 3D) / 3

36 = D

Thus, Ali's dad is currently 36 years old.

Solving for A:

Now, we can solve for A by plugging in 36 for A in the first equation in our system:

(A + 36 = 50) - 36

A = 14

Thus, Ali is currently 14 years old.

Checking the validity of the answer:

  • From our first equation, we know that 14 + 36 is indeed 50, so the solutions are correct for this equation.
  • From our second equation, we know that Ali's dad will be 44 in 8 years, while she will be 22 in 8 years. Because 44 is twice 22, the solutions are also correct for this equation.
User Dallas Clark
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