If a·b·c·d=270, where a, b, c and d are positive integers, and a<b<c<d, which of the following could be the value of d−a? Options
A) 7 B) 10 C) 11 D) 13 E) 15
prime factorize : 270 = 2*3*5*9   Hence a = 2 and d = 9 .   Hence answer is  9 - 2= 
<gadget id="calculator"> 9 - 2</gadget>
<output>7</output>
7   7nswer 7
<result>A</result>
If a·b·c·d=270, where a, b, c and d are positive integers, and a<b<c<d, which of the following could be the value of d−a?