If x, y, and z are positive integers and 2x = 4y = 5z, then the least possible value of x + y + z is	Pick one:	A) 40	B) 50	C) 55	D) 60	E) 19
given 2x=4y=5z   x+y+z in terms of x   = x+(2x/4)+(2x/5) = 38x/20=19x/10   now checking with each of the answers and see which value gives a minimum integer value.   A x = 10/19*40 , not an integer   B,C,E can be ruled out similarly.   D is minimum value as x = 19*10/19= 
<gadget id="calculator">19*10/19</gadget>
<output>10</output>
10   Answer is 19
<result>E</result>
If x, y, and z are positive integers and 2x = 4y = 5z, then the least possible value of x + y + z is