Question 315810
Let {{{d}}} = number of dimes
Let {{{q}}} = number of quarters
given:
(1) {{{d + q = 30}}}
{{{.1d + .25q = 4.95}}}
(2) {{{10d + 25q = 495}}}
Multiply both sides of (1) by {{{10}}} and
subtract (1) from (2)
(2) {{{10d + 25q = 495}}}
(1) {{{-10d - 10q = -300}}}
{{{15q = 195}}}
{{{q = 13}}}
and, since
{{{d + q = 30}}}
{{{d = 30 - 13}}}
{{{d = 17}}}
The person has 17 dimes and 13 quarters