Estimating Whole Numbers

Dayana has 987 books in her library and Julian has 321 books in his library. Estimate the difference in the number of books they have.

• 666

• 789

• 543

• 345

Kayley went to a bookstore and bought books worth 456 dollars. Jimena also bought books from the same bookstore worth 789 dollars. Can you estimate the total amount they spent together?

• 1245

• 1300

• 1500

• 1000

Sandor and Jencarlo went apple picking and collected 2,345 apples. If they round the number of apples to the nearest hundred, how many apples would they have?

• 2,500

• 2,300

• 2,400

• 2,200

Alisson, Kayley, and Yahir participated in a local fundraiser. Alisson contributed 1,234 dollars and Kayley contributed 567 dollars. Can you estimate the total amount they contributed?

• 1,801

• 1,800

• 2,000

• 1,600

What is the best estimate of the number 678

• 670

• 680

• 660

• 650

Norfolk, has a population of 242,628 people. Baltimore, has 376,865 more people than Norfolk. Charleston, has 496,804 less people than Baltimore. Round to the nearest hundred thousand to calculate an estimate.

Mathematical Equivalence

ON

When estimating 1345+ 2789 you should...

• Round both numbers to the nearest ten and add them mentally

• Line both numbers up and solve to find the answer

• Round both numbers to the nearest hundred and add them mentally

• Round both numbers to the million and add them mentally

Estimate the product of 298 and 47 by rounding to the nearest ten.

• 15,000

• 13,000

• 13,860

There are 293 steps to the top of the Leaning Tower of Pisa in Italy.  To the nearest hundred, about how many steps are there?

• 200

• 300

• 290

• 250

Round 89,345 to the nearest thousand.

• 89,000

• 89,300

• 90,000