Answer:
An average of about 450 hours; You could say something along the lines of "If the pianist who practices an average of 45 hours per week practices everyday for three months, they would play for approximately 450 hours total."
Step-by-step explanation:
We could write an equation to make it simpler to figure out, making the number of hours after three months = n, 4 = weeks in a month, 3 = the number of months, and 45 = the number of hours after a week. As an equation, it would look like:
45 * 3 * 4 = n
We know 3 *4 is 12, so the equation becomes 45 * 12 = n.
45 * 12 = 540, therefore the pianist practices an average of approximately 540 hours over a three-month period of time.