Question 1125700
Let {{{ d }}} = number of dimes
Let {{{ q }}} = number of quarters
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{{{ d = q + 7 }}}
{{{ 10d + 25q = 630 }}} ( in cents )
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{{{ 2d + 5q = 126 }}}
By substitution:
{{{ 2*( q + 7 ) + 5q = 126 }}}
{{{ 2q + 14 + 5q = 126 }}}
{{{ 7q = 112 }}}
{{{ q = 16 }}}
And
{{{ d = q + 7 }}}
{{{ d = 16 + 7 }}}
{{{ d = 23 }}}
She has 23 dimes and 16 quarters