Two students combined two different volumes of water. The first student measured 25.4 mL of water using a 100.0 mL graduated cylinder and the second student measured 0.15 mL of water using a 50.00 mL burette. What total volume should be reported after taking into account significant digits and the convention used for rounding?

Question

Quizplus · Accepted Answer

When adding or subtracting measurements, the result should be rounded to the same decimal place as the least precise measurement. In this case, the least precise measurement is 0.15 mL from the burette, which has two decimal places. Therefore, the final answer should also have two decimal places. Adding the two volumes together gives 25.55 mL. Since the digit in the hundredth's place is 5, the whole number should be rounded up to 25.6 mL. Answer choice D is the only one with 25.6 mL.

Two Students Combined Two Different Volumes of Water