What's the radius of the circumference is 314

Its 50. Because circumference is 314. Divide that by 3.14 and you get the diameter. Divide by another 2 and you get 50.

Start by writing a formula-
30=(x+1)+(2x)+(3x+1)
Combine like terms-
30=6x+2
Subtract 2 from both sides
28=6x
Divide both sides by 6
4.666≈x
You can then check this by plugging in 4.666 to your formula and adding to see if it works. Remember, x is roughly equal to 4.666.