Original Question:
100 - [(25/5) x 10] = ?
Note: Always answer what's inside FIRST. In this case, the main ts the brackets, but there's also parenthesis in it too. So solve that.
→100 - [(5) x 10] = ?
Now, solve what's inside the brackets.
→100 - [50] = ?
Well, you can get rid of the brackets.
→100 - 50 = ?
Subtract!
→100 - 50 = 50
Solution:
50