The function f is defined for each positive three-digit integer n by f(n)=2x3y5zf(n)=2x3y5z , where x, y and z are the hundreds, tens, and units digits of n, respectively. If m and v are three-digit positive integers such that f(m)=9f(v), them m-v=?  Answers:
A) 8	B) 9	C) 18	D) 20	E) 80
Soln:-   m=xyz   v=pqr   m-v = 100(x-p) + 10(y-q) + (z-r)............................(1)   f(m)= 2^x*3^y*5^z   f(v)= 2^p*3^q*5^r   Given that,   f(m) = 9 f(v)   =&gt; 2^x*3^y*5^z = 9* 2^p*3^q*5^r   =&gt; 2^x*3^y*5^z = 3^2*2^p*3^q*5^r   =&gt; 2^x*3^y*5^z = 2^p*3^(q+2)*5^r   =&gt; 2^[x-p]*3^[y-q-2]*5^[z-r] = 1   =&gt; 2^[x-p]*3^[y-q-2]*5^[z-r] = 2^0*3^0*5^0   (x-p)=0   (z-r)=0   (y-q)=2   Substituting the above values in equation (1).   m-v = 100(x-p) + 10(y-q) + (z-r)   =&gt; 0 + 10*2 + 0= 
<gadget id="calculator">0 + 10*2 + 0</gadget>
<output>20</output>
&gt;20   ANSWER:20
<result>D</result>
The function f is defined for each positive three-digit integer n by f(n)=2x3y5zf(n)=2x3y5z , where x, y and z are the hundreds, tens, and units digits of n, respectively. If m and v are three-digit positive integers such that f(m)=9f(v), them m-v=?