If x is equal to the sum of the integers from 40 to 50, inclusive, and y is the number of EVEN integers from 40 to 50, inclusive, what is the value of x+y ?  Choose one:	A) 171	B) 281	C) 391	D) 501	E) 613

Rationale: "sum s = n / 2 { 2 a + ( n - 1 ) d } = 11 / 2 { 2 * 40 + ( 11 - 1 ) * 1 } = 11 * 45 = 495 = x number of even number = ( 50 - 40 ) / 2 + 1 = 6 = y x + y = 495 + 6 = 501 d"
Answer: D