If 5400 mn = k^4, where m, n, and k are positive integers, what is the least possible value of 5m + n?  Answers.
A) 65
B) 18
C) 20
D) 25
E) 33
k^4=5400∗mn   k^4=3^3.2^3.5^2.mn   In order to make RHS a perfect power of 4, we require it to be multiplied by 3, 2 &amp; 5^2   mn=3.2.5^2   mn = 150 = 10 * 15 (Least possible)   65nswer =5* 10 + 15= 
<gadget id="calculator">5* 10 + 15</gadget>
<output>65</output>
65   65NSWER:65
<result>A</result>
If 5400 mn = k^4, where m, n, and k are positive integers, what is the least possible value of 5m + n?