Lesson Worksheet: Estimating Calculations by Rounding to One, Two, or Three Significant Figures Mathematics

In this worksheet, we will practice estimating calculations by rounding to a specified number of significant figures throughout the calculation.


The following figure shows Mason’s garden. Estimate the area of the figure by rounding to 2 significant figures.


Consider the given table and book.

By rounding the book’s dimensions to 1 significant figure, approximately how many books can you put on the table to cover it all?


Estimate 122×251 by rounding both numbers to 1 significant figure.


By rounding the lengths of the sides of the following triangle to 1 significant figure, find the perimeter.


You have 16 dollars and you need to divide this money equally among three people. By rounding the result to 2 significant figures, approximately how much will each one get?


By rounding all of the numbers to 2 significant figures, which calculation would you carry out to estimate 156+(2,432÷123)?

  • A160+(2,400÷120)
  • B150+(2,400÷120)
  • C16+(24÷12)
  • D160+(2,400÷12)
  • E160+(2,500÷120)

What is the estimated answer to 156+(2,432÷123)?


Estimate 35×560.36 by rounding each number to 1 siginificant figure.


Natalie bought 2.5 kilograms of tomatoes. If one kilogram costs 2.15 pounds, round each number to 1 significant figure to estimate how much Natalie paid in total.


Estimate 15.45×120.3 by rounding each number to 3 significant figures.


Estimate 632×2352,200 by rounding each number to 1 siginificant figure.

This lesson includes 63 additional question variations for subscribers.

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