3rd Grade Rounding to Estimate Differences Worksheet: 3 Stories

"How many more?" is a question about a difference, and rounding makes it quick. This 3rd grade rounding to estimate differences worksheet has three word problems. In the first, Mercy and two sisters pick apples in an orchard. In the second, Jerry gives away pennies from his bank, while in the third, a furniture store sells plastic chairs and tables. Each problem tells your child where to round: to the nearest hundred, thousand or ten, so your child rounds the numbers first and then subtracts. Two girls stand by a pile of red fruit, and a boy sits near a sofa. Page two shows every step in pink.

Three estimates, step by step

The answers are about 100 apples, 2,000 pennies and 300 chairs. In problem 1, Jane picks 349 + 160 = 509 apples and Jannet picks 509 − 67 = 442. Rounded to the nearest hundred, Jannet has 400 and Mercy has 300, so the estimated difference is about 100. The exact difference is 93, which is close.

In problem 2, 9,672 rounds to 10,000 and 7,992 rounds to 8,000, so Jerry keeps about 2,000. However, rounding to the nearest thousand with 4-digit numbers goes beyond third grade. In problem 3, 396 and 99 round to 400 and 100, which gives 300.

At the table: compare with the exact answer

After each estimate, your child can find the exact difference too. For problem 3, 396 − 99 = 297, and the estimate of 300 is very close. This shows why an estimate is useful: it checks that an exact answer makes sense. The rounding rule stays the same: look at the digit just to the right.

The page has slips to correct. Problem 1 says "67 less apples", but "fewer apples" is right, and it says "her sister, Jane and Jannet" for two sisters. Then problem 3 calls Charles a "sales boy" instead of a salesperson. There are stray spaces in 9, 672 and 7, 992, and the picture shows cherries, not apples.

After the page: how many more pages?

Take two books from a shelf and read their page counts, such as 312 and 187. Your child rounds both to the nearest hundred and subtracts: 300 − 200 = 100, and then they find the exact difference, 125, and compare. Finally, check the three problems with the answer key on page two.