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Kyle is buying gifts for Megan's birthday and needs to stay in budget

Cake = half his money + 36.50
Decorations = half of what he had left + 36.50
Sweets = half of what he had left + 18.25

Now he is out of money, what did he start with?

User Hammerhead
by
7.8k points

1 Answer

4 votes

Answer: Let's start by using algebra to represent the problem.

Let X be the amount of money that Kyle started with.

Then we can create the following equations:

  • Cake = 0.5X + 36.50
  • Decorations = 0.5(X - Cake) + 36.50
  • Sweets = 0.5(X - Cake - Decorations) + 18.25

And we know that he's out of money, so:

  • Cake + Decorations + Sweets = X
  • We can use substitution to solve for X.

Substitute the first equation into the second equation to get:

  • Decorations = 0.5(X - (0.5X + 36.50)) + 36.50
  • Decorations = 0.25X + 9.25

Substitute the first two equations into the third equation to get:

  • Sweets = 0.5(X - (0.5X + 36.50) - (0.25X + 9.25)) + 18.25
  • Sweets = 0.25X + 4.75

Substitute all three equations into the fourth equation to get:

(0.5X + 36.50) + (0.25X + 9.25) + (0.25X + 4.75) = X

Simplify and solve for X:

  • 1X + 50.50 = X
  • 50.50 = 0.5X
  • X = 101

Therefore, Kyle started with $101.

User Labinot
by
7.9k points