Final Answer:
The result of 70 - 50 + 20 is 60, thus the correct option is D.
Explanation:
The mathematical equation 70 - 50 + 20 follows the order of operations, which is Parentheses, Exponents, Multiplication, Division, Addition and Subtraction (PEMDAS). Starting with the parentheses, there are none to be evaluated, and then we move on to the exponents. Again, there are no exponents to be evaluated in this equation. Next, we move on to multiplication and division. There is neither multiplication nor division present in this equation, so we move on to addition and subtraction.
In this equation, the addition and subtraction are both present, so we must evaluate it from left to right. We start by evaluating 70 - 50, which yields 20. We then add this result (20) to the number at the end of the equation (20), which yields a total of 40. Therefore, the answer to the equation 70 - 50 + 20 is D. 60.