let's first off convert those mixed fractions to improper fractions, then get their difference.
![\bf \stackrel{mixed}{1\frac{1}{2}}\implies \cfrac{1\cdot 2+1}{2}\implies \stackrel{improper}{\cfrac{3}{2}}~\hfill \stackrel{mixed}{2\frac{1}{10}}\implies \cfrac{2\cdot 10+1}{10}\implies \stackrel{improper}{\cfrac{21}{10}} \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ \cfrac{21}{10}-\cfrac{3}{2}\implies \stackrel{\textit{using the LCD of 10}}{\cfrac{(1)21-(5)3}{10}}\implies \cfrac{21-15}{10}\implies \cfrac{6}{10}\implies \cfrac{3}{5}](https://tex.z-dn.net/?f=%5Cbf%20%5Cstackrel%7Bmixed%7D%7B1%5Cfrac%7B1%7D%7B2%7D%7D%5Cimplies%20%5Ccfrac%7B1%5Ccdot%202%2B1%7D%7B2%7D%5Cimplies%20%5Cstackrel%7Bimproper%7D%7B%5Ccfrac%7B3%7D%7B2%7D%7D~%5Chfill%20%5Cstackrel%7Bmixed%7D%7B2%5Cfrac%7B1%7D%7B10%7D%7D%5Cimplies%20%5Ccfrac%7B2%5Ccdot%2010%2B1%7D%7B10%7D%5Cimplies%20%5Cstackrel%7Bimproper%7D%7B%5Ccfrac%7B21%7D%7B10%7D%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20%5Crule%7B34em%7D%7B0.25pt%7D%5C%5C%5C%5C%20%5Ccfrac%7B21%7D%7B10%7D-%5Ccfrac%7B3%7D%7B2%7D%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Busing%20the%20LCD%20of%2010%7D%7D%7B%5Ccfrac%7B%281%2921-%285%293%7D%7B10%7D%7D%5Cimplies%20%5Ccfrac%7B21-15%7D%7B10%7D%5Cimplies%20%5Ccfrac%7B6%7D%7B10%7D%5Cimplies%20%5Ccfrac%7B3%7D%7B5%7D)
now, the original amount, 3/2, if that is the 100%, what is 3/5 off of it in percentage?

Answer:
C
Step-by-step explanation:
The answer to the given question above would be option A. Based on the given map shown above which is a typical flight path between Seattle and London, the reason why the path goes over the Arctic is that, it is the shortest path. Hope this answers your question.
determinant: 
(a) 
D<0 means there are no real roots. there are two complex roots with imaginary components.
(b) D=16+20=36>0
D>0 means there are two real roots
(c) D = 20^2-4*4*25 = 0
D=0 means there is one real root with multiplicity 2