Question

Dave tried to evaluate 55 – 15 + 20 step-by-step.

55 - 15 + 20

Step 1: =40 + 20

Step 2: = 20

Find Dave’s mistake

Choose 1 answer:

A: step 1
B: step 2
C: Dave did not make a mistake

Answer 1

Step 2

Explanation:

In step 2 the expression was 40+20 which would have been 60 but he might have thought addition sign was subtraction so he did 40-20 which is 20 so he is wrong made mistake in step 2