Question

Which two mathemetical signs should be interchanged to correct the given eqution 3+4-5+7-8=9?

Answer 1

Answer:

The minus sign between 7 and 8 should be interchanged with the plus sign between 3 and 4.

This makes it 3 - 4 -5 + 7 + 8 = 9, where both LHS and RHS are equal.

Answer 2

3-4-5+7+8=3-9+7+8=10-9+8=1+8=9