His average speed is 40mph you get your answer by dividing 80 by 2, or or you could do what is half of 80 which is 40. So Mr.Campbell average speed is 40mph
Step-by-step explanation: In this case it is easier to imagine it on the number line: the y coordinates are the same, so the distance is only in x direction. On the positive side it is 2 2/3 to zero and on the negative, 1 1/3 to zero. Total is 1 1/3 + 2 2/3 = 4. Or the proper writing: 2 2/3 - (-1 1/3) = 4