Final answer:
Stacy can paint the entire room in 4 hours. She paints 1/4 of the room per hour, so after 3 hours, she has 1/4 left to paint, which takes an additional hour. Option C is correct.
Step-by-step explanation:
The student asked how long it will take Stacy to paint the entire room if she can paint 3/4 of it in 3 hours. To solve this, we need to find the rate of painting per hour and then calculate the time needed for the remaining quarter of the room.
Stacy paints 3/4 of the room in 3 hours. This means that in one hour, she can paint 1/4 of the room. (3/4 divided by 3 equals 1/4). Therefore, it would take her one additional hour to paint the remaining 1/4 of the room. In total, Stacy will need 4 hours to paint her entire room at the same rate.
The correct answer is c) 4 hours.
To find out how long Stacy will take to paint the entire room, we can set up a proportion. We know that she can paint 3/4 of the room in 3 hours, so we can set up the equation: (3/4) / 3 = 1 / x. Cross multiplying, we get (3/4) * x = 3 * 1. Simplifying further, (3x/4) = 3. Multiply both sides of the equation by 4 to get rid of the fraction, resulting in 3x = 12. Divide both sides by 3 to solve for x, giving us x = 4.