If #-84# is less-than #(<)# #7c#, then #7c# must be higher in value than #-84#.
So #7# multiplied by what #= -84#? Using a calculator, trial and error, or by dividing #-84# by #7#, you will find that
#7 * (-12) = -84#
So your answer is: '#c# is more than #-12#' OR '#c > -12#' as any number higher in value than #-12# could equal #c#.
Hope this helps!