When you took a 50 and gave back 25, your net change was 125. 3 25s and a 50.
Then you got a 100.
If you return 3 25s you have no more 25s left if someone gives you a 50.
But if you return a 50 and a 25, you still got two more 25s to hand out in case you get a 50.
Don't just count 25s, 50s are a kind of change too!

Your code is suboptimal.
When you needed to pay back 75, you could have given a 50 and a 25 instead of 3 25s.
That would leave you with 2 25s to use on further transactions.
The correct answer is "YES".