The sum of two numbers is 72, and one of them is 12 more than the other. What are the two numbers?  Pick one
A) 36 - 48  B) 50 - 34  C) 60 - 24  D) 30 - 42  E) 21 - 63

Rationale: "in this problem , we are asked to find two numbers . therefore , we must let x be one of them . let x , then , be the first number . we are told that the other number is 12 more , x + 12 . the problem states that their sum is 72 : word problem = 72 the line over x + 12 is a grouping symbol called a vinculum . it saves us writing parentheses . we have : 2 x = 72 â ˆ ’ 12 = 60 . x = 60 / 2 = 30 . this is the first number . therefore the other number is x + 12 = 30 + 12 = 42 . the sum of 30 + 42 is 72 . d"
Answer: D