Question 995086
Your description does not have enough information.

You only have enough for  {{{0.10d+0.25q=14.7}}} and this can be simplified or adjusted into {{{2d+5q=294}}}.


Your shown equation (wrong because of a decimal mistake) implies a count of coins to be 72, so that {{{d+q=72}}}.  If this is the missing part of your description, then now you know you have a system of equations equivalent to 
{{{highlight_green(system(2d+5q=294,d+q=72))}}} which should not be difficult to solve.



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q=50
d=22