Rule1: Always start with the inner most bracket first
13+5 = 18 so put 18 instead of that in the expression
Now the innermost bracket is (11-18)
Now we calculate 11-18, which is equal to -7 hence we put -7 instead of that,
here is the important part which most people miss. When we subtract a negative value from a number its the same as adding the positive value. we are subtracting -7(the negative value) which is the same as adding the positive value to it. Hence we can get to the below expression
Now -5 + 7 is equal to +2 hence the answer is +2
May 15th, 2015
Are you studying on the go? Check out our FREE app and post questions on the fly!