Whats the rest of the question?
You can use the measure of 112 on the similar shape to find b, as they are same side exterior angles. From there, you can find both a and c, because a/b and b/c are supplementary angles.
a = 68 degrees
c = 68 degrees
First off, we'll convert the mixed fractions to "improper",

30 times 30 plus 45 minus 456 is 489