Question 218682
Let {{{j}}} = number of nickels Juan has
Let {{{s}}} = number of nickels Sam has
Let {{{c}}} = number of nickels Carlos has
given:
(1) {{{j = 2s + 4}}}
(2) {{{c = 3s - 2}}}
(3) {{{j + s + c = 190/5}}} (in nickels)
Substitute (1) and (2) in (3)
{{{2s + 4 + s + 3s - 2 = 190/5}}}
{{{6s + 2 = 190/5}}}
{{{6s = 38 - 2}}}
{{{6s = 36}}}
{{{s = 6}}}
Sam has 6 nickels
check answer:
and
{{{j = 2s + 4}}}
{{{j = 2*6 + 4}}}
{{{j = 16}}}
also
{{{c = 3s - 2}}}
{{{c = 3*6 - 2}}}
{{{c = 16}}}
and
{{{j + s + c = 190/5}}}
{{{16 + 6 + 16 = 190/5}}}
{{{38 = 38}}}
OK