What is the smallest positive integer x such that 720-x is the cube of a positive integer
Choices
A) 5 B) 7 C) 47 D) 9 E) 12
Given 738-x is a perfect cube   so we will take 729 = 9*9*9   738-x = 729   x =738-729= 
<gadget id="calculator">738-729</gadget>
<output>9</output>
9   correct option is 9
<result>D</result>
What is the smallest positive integer x such that 720-x is the cube of a positive integer