The difference of a larger number and a smaller number is 6. The sum of the larger number and twice the smaller is 15. What is the larger number?
Choose the correct choice from the following answers.
A) 7 B) 8 C) 9 D) 10 E) 11

Rationale: let x be the larger number and y be the smaller number . x - y = 6 x + 2 ( y ) = 15 solve by substitution : y = x - 6 x + 2 ( x - 6 ) = 15 x + 2 x - 12 = 15 3 x = 27 x = 9 the larger number is 9 , so answer c is correct .
Answer: C