Question

report the measurement correctly. (the measurement should reflect the increments on the instrument). do not include units in your answer

Explanation:

Step1: Determine the scale increment

The ruler has major marks at 40, 50, 60, 70. Between 40 - 50, 50 - 60, 60 - 70, there are 10 small divisions. So each small division is $\frac{10}{10} = 1$ unit.

Step2: Read the measurement

The arrow is at the 51st mark (since 50 is the 50th mark and one more small division). So the measurement is 51.

Answer:

51