Nasim bought stock in a company two years ago that was worth xx dollars. During the first year that he owned the stock, it decreased by 28%. During the second year the value of the stock increased by 35%. Write an expression in terms of xx that represents the value of the stock after the two years have passed.

1 answer

To calculate the value of the stock after two years, we will go through each year's change step-by-step.

  1. Initial Value: The initial value of the stock is \( xx \).

  2. First Year: The stock decreases by 28%. The value after the first year can be calculated as follows: \[ \text{Value after first year} = xx - 0.28 \cdot xx = xx(1 - 0.28) = xx \cdot 0.72 \]

  3. Second Year: The stock increases by 35% in the second year. We will use the value at the end of the first year as the base for the increase: \[ \text{Value after second year} = \text{Value after first year} + 0.35 \cdot \text{Value after first year} = \text{Value after first year} \cdot (1 + 0.35) \] Substituting the value after the first year: \[ \text{Value after second year} = (xx \cdot 0.72) \cdot 1.35 \]

  4. Final Expression: Now we can simplify this expression: \[ \text{Value after second year} = xx \cdot 0.72 \cdot 1.35 \]

Calculating \( 0.72 \cdot 1.35 \): \[ 0.72 \cdot 1.35 = 0.972 \]

So the final expression for the value of the stock after two years is: \[ \text{Final Value} = xx \cdot 0.972 \]

Thus, the expression that represents the value of the stock after the two years have passed is: \[ 0.972xx \]