Question: There are 336 books in a library. On Monday, 124 books are taken out. On Tuesday, 22 books are brought back. How many books are there now?
Answer with step-by-step thinking: At the end of Monday, there are 336 - 124 = 212 books left. At the end of Tuesday, there are 212 + 22 = 234 books.
So the answer is 234.

Question: Patrick is half the age of his elder brother Robert. If Robert will turn 30 after 2 years, how old is Patrick now?
Answer with step-by-step thinking: The age of Robert now is 30 - 2 = 28 years old. So, Patrick is 28 / 2 = 14 years old.
So the answer is 14.

Question: Elliott drew a right-angle triangle on his book. It had a base of 4 inches, a height of 3 inches and a certain length of the hypotenuse. What was the length of the perimeter of the triangle that he drew?
Answer with step-by-step thinking:
Since the hypotenuse of a triangle is found by the square root of the base squared plus the height squared. The square of the base of the first triangle is 4 * 4 = 16 square inches. The square of the height of the first triangle is 3 * 3 = 9 square inches. The sum of the squares of the base and the height of the first triangle is 16 + 9 = 25. The square root of the sum of the base and the height of the first triangle, which is the hypotenuse of the triangle, is 25 = 5 inches. Since the perimeter of a triangle is found by adding the sides of the triangle, the base and height of the triangle sum up to 3 + 4 = 7 inches. If you add the hypotenuse of the triangle the perimeter of the triangle becomes 7 + 5 = 12 inches.
So the answer is 12.