Problem number 7. Omar wants to write the 4 digits 2, 0, 2, and 5 in the 4 boxes of the calculation shown. What is the smallest result that Omar could get? So in this problem, we need to minimize the value of this subtraction and addition. And in particular, we should put the largest digits in boxes that are after a minus sign, because that means that a really large number is going to be taken away from the total. In the opposite direction, we want to put small numbers in boxes that are after a plus sign, because we don't want to add too much to the result, because we want the result to be as small as possible. In this case, the largest two digits are 2 and 5, so those should go after the minus signs, and the remaining digits, 2 and 0, should go after the plus signs. So for example, you can put the digits in the order 0, minus 2, plus 2, minus 5. The 2 and 5 are after minus signs, and the 0 and 2 are after plus signs. If you calculate the result, you will get negative 5, which is indeed the smallest result that you can get. That means that the answer is C, negative 5.

smallest result

subtraction and addition

minimize value

digit placement

negative result