Leann has stickers. She gives her friend half, and then her brother gives her 8 new ones. She ends up with 12 stickers. How many did she start with? Identify the operations needed to solve this problem.

Addition and division, subtraction and division, addition and multiplication, subtraction and multiplication

1 answer

To solve the problem, let's define the unknown variable and step through the operations:

Let \( x \) be the number of stickers Leann started with.

  1. Leann gives half of her stickers to her friend: \[ \text{Stickers left} = \frac{x}{2} \]

  2. Her brother gives her 8 new stickers: \[ \text{Total stickers now} = \frac{x}{2} + 8 \]

  3. We know that this total equals 12: \[ \frac{x}{2} + 8 = 12 \]

To solve for \( x \):

  • Subtract 8 from both sides: \[ \frac{x}{2} = 12 - 8 \] \[ \frac{x}{2} = 4 \]

  • Multiply both sides by 2: \[ x = 4 \times 2 \] \[ x = 8 \]

Leann started with 8 stickers.

Now, identifying the operations used to solve the problem:

  1. Subtraction (8 from 12)
  2. Division (when determining half of \( x \))
  3. Multiplication (to solve for \( x \))

The correct pair of operations employed in the problem is subtraction and multiplication.