a' and 'b' are positive integers such that their LCM is 20 and their HCF is 1. What is the difference between the maximum and minimum possible values of 'a - b'? Answers:
A) 28
B) 29
C) 34
D) 38
E) 36
possible values of a and b can be 5,4; 4,5 and 1,20; 20,1   maximum possible value for a-b is   20-1= 
<gadget id="calculator">  20-1</gadget>
<output>19</output>
19   minimum possible value for a-b is 1-20=-19   19-(-19)= 
<gadget id="calculator">19-(-19)</gadget>
<output>38</output>
38 ans is 38
<result>D</result>
a' and 'b' are positive integers such that their LCM is 20 and their HCF is 1. What is the difference between the maximum and minimum possible values of 'a - b'?