Answer:

Step-by-step explanation:
step 1
Find the circumference of the complete circle
The circumference is equal to

we have

substitute


step 2
Find the measure of the arc length for a central angle of 280 degrees
Remember that the circumference subtends a central angle of 360 degrees
so by proportion

step 3
Find the perimeter of the playground

Multiply by 3

Round to the nearest integer

Answer:
Divide by 1
Step-by-step explanation:
-4/1
The answer is a = 3/4 = 0.75
First get rid of the paranthesis,

Then set the denominators equal:

Then remove the denominators and solve:

Eliminate -12a^2 by adding 12a^2 to both sides:

Take the fourth root of them or take the square root twice:
![\sqrt[4]{256 {a}^{4} } = \sqrt[4]{81} \\ 4a = 3](https://tex.z-dn.net/?f=%20%5Csqrt%5B4%5D%7B256%20%7Ba%7D%5E%7B4%7D%20%7D%20%20%3D%20%20%5Csqrt%5B4%5D%7B81%7D%20%20%20%5C%5C%20%204a%20%3D%203)
Divide both sides by 4:
1 and 3/5 hours since he paints 1/4 every 2/5 an hour simply times 2/5 by 4/1 and get 8/5 which is equal to 1 and 3/5 an hour