Question 1115062
{{{10d+5n+p=110}}}
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{{{n/p=3}}}
{{{n=3p}}}
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{{{d=p-2}}}
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Substituting for n and d,
{{{highlight_green(10(p-2)+5*3p+p=110)}}}-----one equation in just one variable, p.  Solve and then evaluate n and d.