The first box should be correct
30 + c = 40
the correct answer is c 7 feet i hope this helps you out

enters the irrational number category.
Integers numbers are the numbers without decimals between -infinity and infinity.
Natural numbers are the whole numbers from 1 to infinity.
Whole numbers are natural numbers + 0.
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!