Question: 
Write a function to calculate volume of a tetrahedron.


Model's Code:
def volume_tetrahedron(side_length):
    return (side_length ** 3) / (6 * (2 ** 0.5))



Sample Correct Code:
import math
def volume_tetrahedron(num):
	volume = (num ** 3 / (6 * math.sqrt(2)))	
	return round(volume, 2)


Asserts:
assert volume_tetrahedron(10)==117.85
assert volume_tetrahedron(15)==397.75
assert volume_tetrahedron(20)==942.81


Tests:
Test 1 of 3: FAIL: AssertionError()

Test 519 of 974: 382/519 (73.60308285163777%): failed