The highlighted sector is exactly 3/4 of the circle area, because 
is 3/4 of 
which is a complete rotation.
Since you are given the radius, you can compute the area as
So, 3/4 of this area would be 
squared cm.
The remaining sector, of course, is 
squared cm.
The last integer is z, then the other two are z-1 and z-2.
The sum is therefore
(z-2)+(z-1)+z=3z-3.
Your answer would be 74 if you are looking for the answer.
Since all the terms are odd, the last four terms would be 115+117+119+121
115 + 117 = 232
232 + 119 = 351
351 + 121 = 472
Answer: 472
I hope this helped :)
