Question 827161
so being that there are 4 more quarters the dimes that's 1 dollar that we already know is made up of just quarters, {{{3.80-1.00=2.80}}}
so really we are looking for how many quarters and dimes make up 2.80, but there has to be an equal amount of quarters and dimes for the other 4 quarters to stay the only 4 quarters more then dimes
so at this point the amount of quarters is the same as the amount of dimes that will add up to 2.80
{{{q=d}}}
{{{.25q+.10d=2.80}}}
use substitution
{{{.25d+.10d=2.80}}}
add like terms
{{{.35d=2.80}}}
divide by .35
{{{d=8}}}
since there are 4 more quarters then dimes
{{{8+4=q}}}
{{{12=q}}}
there are 8 dimes and 12 quarters