Based on the given situation above, the answer would be: either of two discounts can be applied first to save money because both have the same results. Here is the solution:
First solution:
Let x = original price
Do the 25% discount first, then the 10% discount
Apply the first discount
x - 0.25x = 0.75x
Then apply the second discount
0.75x - 0.10*0.75x = 0.675*x
So the result would be, you're paying 67.5% of the original price and get an overall discount of 100 - 67.5 = 32.5% off
Second solution:
Do the 10% discount first, then the 25% discount
Apply the first discount
x - 0.10x = 0.90x
Then apply the second discount
0.90x - 0.25*0.90x = 0.675*x
Still, you get the same price
