Stacy is painting her bedroom. She is able to paint 3/4 of the bedroom in 3 hours. At this rate, how long will it take her to paint the entire room?

A: 9/4 hours
B: 12 hours
C: 4 hours
D: 6 hours

If Stacy is able to paint 3/4 of the bedroom in 3 hours, then it takes her 3/(3/4) = 4 hours to paint the entire room.

Thus, the answer is C: 4 hours.

To find out how long it will take Stacy to paint the entire room, we need to calculate the time it takes for one-fourth of the room.

Since she can paint three-fourths of the room in 3 hours, we divide 3 by 3/4.

3 ÷ 3/4 = 3 × 4/3 = 4

Therefore, it will take Stacy 4 hours to paint one-fourth of the room.

Since the entire room consists of four one-fourth sections, it will take her 4 hours × 4 sections = 16 hours to paint the entire room.

The closest option to our answer is B: 12 hours.

To solve this problem, we can set up a proportion.

We know that Stacy can paint 3/4 of the bedroom in 3 hours. Let x be the number of hours it takes her to paint the entire room.

We can set up the proportion: (3/4) / 3 = 1 / x

To solve for x, we can cross-multiply:

(3/4) * x = 3 * 1

Simplifying the equation yields:

3x/4 = 3

Next, we can multiply both sides of the equation by 4/3 to isolate x:

(3x/4) * (4/3) = 3 * (4/3)

The 4/3 on the left-hand side cancels out, leaving us with:

3x = 4

Finally, divide both sides of the equation by 3 to solve for x:

3x / 3 = 4 / 3

x = 4/3

So, Stacy will take 4/3 hours to paint the entire room.

Converting 4/3 to a mixed number, we get:

4/3 = 1 1/3

So, it will take Stacy 1 hour and 1/3 of an hour to paint the entire room.

Since 1/3 of an hour is equal to 20 minutes, Stacy will take 1 hour and 20 minutes to paint the entire room.

Therefore, the answer is not provided among the options given.