Charla wants to cover a certain rectangular area of her driveway with a picture using chalk. If she completes 2/3 of the area in 1/2 hour, how long will it take her to complete the entire picture?

Since Charla completes 2/3 of the area in 1/2 hour, this means that she completes 1/3 of the area in 1/2 hour, which can be written as 1/3 * 1/2 = 1/6 of the area in 1/2 hour.

Therefore, it will take Charla 6 * 1/2 = <<6*1/2=3>>3 hours to complete the entire picture. Answer: \boxed{3}.

To find out how long it will take Charla to complete the entire picture, we need to determine the remaining area that needs to be covered and how long it takes her to complete this remaining area.

Given that Charla completes 2/3 of the area in 1/2 hour, this means that there's still 1/3 of the area remaining to be covered.

To find the time it will take to complete this remaining area, we can set up a proportion:

(1/2 hour) is to (2/3 of the area) as (x hours) is to (1/3 of the area)

(1/2) / (2/3) = x / (1/3)

Simplifying this equation:

(1/2) * (3/2) = x * (3/1)

3/4 = 3x/1

Cross-multiplying:

3x = 4 * 3

3x = 12

Dividing both sides by 3:

x = 12/3

x = 4 hours

Therefore, it will take Charla 4 hours to complete the entire picture.

To solve this problem, we need to determine how long it takes Charla to complete 1/3 of the area (since she has already completed 2/3 in 1/2 hour).

To do this, we can set up a proportion between the completed area and the time taken:
2/3 area / 1/2 hour = 1/3 area / t hour

Cross-multiplying, we get:
(2/3) * t = (1/3) * (1/2)

Simplifying further, we have:
2t/3 = 1/6

To find the value of t, we can multiply both sides of the equation by 3/2:
(2t/3) * (3/2) = (1/6) * (3/2)

This gives us:
t = 1/4

Therefore, it will take Charla 1/4 of an hour or 15 minutes to complete the remaining 1/3 of the area.

3/4 of an hour