Question 1114004
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The solution by the other tutor using substitution is fine....<br>
However, when the two equations we start with are both of the form {{{Ax+By=C}}}, I think a solution using elimination is easier than a solution using substitution.<br>
(1) {{{a+b = 1250}}}  total number of people is 1250
(2) {{{25a+75b = 61250}}}  total cost is 61,250<br>
Multiply equation (1) by 25 and subtract from equation (2):
(3) {{{25a+25b = 31250}}}
(4) {{{50b = 30000}}}
{{{b = 600}}}<br>
The number of adults is 600; so the number of children is 1250-600=650.<br>
Of course both methods are valid.  Try both and find out which you like better.