The following water measurements were made: 18 mL of water were measured with a beaker, 128.7 mL of water were measured in a graduated cylinder and 23.45 mL of water were measured in a buret. All of these water samples were then poured together in one container. What total volume of water should be reported, when significant digits are taken into account?

170 mL

Explanation:

The total volume to be reported should be 170 mL.

According to the significant rule in mathematical operations, final answers are usually reported to reflect the accuracy of the least accurate number.

In this case, the least accurate of all the volumes has zero significant digits after the decimal, hence, the final answer after the mathematical operation should also have no significant digits after the decimal.

           18 + 128.7 + 23.45 = 170.15

Therefore, the total volume to be reported when significant digits are taken into account would be 170 mL.