If x, y, and z are positive integers and x = 5y = 9z, then the least possible value of x + y - z is Pick one
A) 33 B) 40 C) 49 D) 61 E) 84
x + y - z = x/5 + x - x/9   = (45 + 9 - 5 )x/45 = 49x/45   49 is not divisible by 45, so for least value, x = 45   49
<result>C</result>
If x, y, and z are positive integers and x = 5y = 9z, then the least possible value of x + y - z is