Ticket at a rugby leaque game cost $2.00 for children and $3.00 for adult.

$2319 was collected after selling 889 tickets.
How many adult tickets were sold?

2 answers

use what they have told you.
a+c = 889
3a+2c = 2319
Now just solve for a.
3a+2c = 2319
2a+2c = 1778
subtract, and you have
a = 541
How do you get 2 in 2a + 2c =1778