Approximately 2945.24 units
For this case we have that by definition
equals 180 degrees.
We must convert 135 degrees to radians, then:

Rounding off we have:
2.4 radians.
Answer:
2.4 radians
Easier than it looks, all you have to do is first subtract 13 from 299. You should get 286. Then, you just divide this number by two to get 143. Finally, since it asks for ZENA'S average, you add the 13 back to 143 to get the final answer of the average number of pins Zena took down, which is 156!
Let x be the number of children
Let y be the number of adults
x + y = 4
4x + 7y = 19