Since we know that 1/4 is equal to 25%, or 0.25 in decimal form, we are able to work with 0.75 in the expression.
We are told to use j as the original price of the jeans, so we can set up the expression:
to represent the cost of the jeans with the discount.
Then to simplify, we simply take out j as a common factor, and solve what's in the parentheses:
or
Using this equation, we can solve for the b part of the question. If the pair of jeans originally costs $60, plug in 60 to where j is in the expression:
Therefore, the cost of the jeans after the discount is C) $45.