Deepa bought stock in a company two years ago that was worth xx dollars. During the first year that she owned the stock, it increased by 9%. During the second year the value of the stock decreased by 27%. Write an expression in terms of xx that represents the value of the stock after the two years have passed.

1 answer

To find the expression representing the value of Deepa's stock after two years, we start with the initial value of the stock, which is \( xx \) dollars.

Step 1: Calculate the value after the first year. During the first year, the stock increased by 9%. The new value after the increase can be calculated as follows:

\[ \text{Value after Year 1} = xx + (0.09 \times xx) = xx(1 + 0.09) = xx(1.09) \]

Step 2: Calculate the value after the second year. During the second year, the stock decreased by 27%. We will apply this decrease to the value at the end of the first year:

\[ \text{Value after Year 2} = \text{Value after Year 1} - (0.27 \times \text{Value after Year 1}) \]

Substituting the value from Year 1:

\[ \text{Value after Year 2} = xx(1.09) - (0.27 \times xx(1.09)) = xx(1.09)(1 - 0.27) = xx(1.09)(0.73) \]

Final Expression: Now we can multiply out this expression:

\[ \text{Value after 2 years} = xx(1.09 \times 0.73) \]

Calculating \( 1.09 \times 0.73 \):

\[ 1.09 \times 0.73 = 0.7967 \]

Thus, the expression for the value of the stock after two years is:

\[ \text{Value after 2 years} = 0.7967xx \]

So the final expression that represents the value of the stock after two years is:

\[ 0.7967xx \]