Let's assume
x represents the number of $25 tickets
y represents the number of $50 tickets
A total of 1,250 tickets
so, we get

So, cost of $25 tickets is 25x
So, cost of $50 tickets is 50y
Total cost of tickets =(cost of $25 tickets)+(cost of $50 tickets)
Total cost of tickets =25x+50y
we are given
worth $50,000, were sold
so, we get equation as

we get system of equations as

..............Answer