Question 124704
a = number of adult tickets
c = number of child tickets
{{{10a + 4c = 234}}}
{{{a + c = 30}}}
{{{a = 30 - c}}}
{{{10(30 - c) + 4c = 234}}}
{{{300 - 10c + 4c = 234}}}
{{{-6c = -66}}}
{{{c = 11}}}
Ther were 11 children at the play