5th Grade Estimate With Decimals worksheets

About this worksheet

Estimating with decimals asks a fifth grader to round first and calculate second, which feels backward to a child who has just learned to add and multiply decimals exactly. The point of an estimate is speed and a reasonableness check, not precision: rounding 6. 7 and 3. 2 to 7 and 3 before adding gives an estimated sum of 10 in seconds, and that estimate is what catches a misplaced decimal point in an exact answer later. This worksheet asks your child to round one or two decimals to the nearest whole number and then estimate a sum, a difference, or a product, and it also asks your child to judge whether a given estimate is reasonable.

A common mistake is doing the exact calculation first and calling the precise answer an estimate, which defeats the purpose of estimating as a quick check. Another is rounding only one of the two numbers and forgetting the other. Encourage your child to look at the digit right after the decimal point to decide whether a number rounds up or down, and to say the rounded numbers out loud before adding, subtracting, or multiplying them.

What your child will learn

• Round a decimal to the nearest whole number
• Estimate a sum of two decimals
• Estimate a difference of two decimals
• Estimate a product of two decimals
• Judge whether an estimate is reasonable