SOLUTION: Simplify, leaving only positive exponents in final answer: {{{(p^2qr^3)/(4p^(-1)q^2r^(-1))^2}}}

To remove the parentheses, first make sure every factor

inside the parentheses has its exponents showing, so we'll

even put a 1 exponent for the 4, since it's a factor inside

the parentheses:







Remove the parentheses on the bottom by multiplying every

exponent inside the parentheses by the exponent outside the

parentheses:











Get rid of the negative exponents (in red)







by moving the factors from the bottom to the top and 

changing the sign of their exponents to positive:







Now we 

1. add the exponents of  in the top 

2. add the exponents of  in the top 

3. do the exponent 







Give the  in the top the exponent 1:







Subtract the exponents of q, larger minus smaller, getting 

putting the result  in the bottom because the larger exponent

 was in the bottom.  (Eliminate q from the top, of course)







That's as far as it will simplify.



Edwin