Estimate Sums

Learn to quickly find approximate answers by rounding numbers!

What is Estimating Sums?

Estimating sums means finding a quick, approximate answer to an addition problem.
Instead of calculating the exact total, we round numbers to make them easier to work with mentally. This skill is super helpful in real life when you need a quick answer or want to check if your exact calculation makes sense!

How to Estimate Sums

1️⃣ Round each number to the nearest ten or hundred

2️⃣ Add the rounded numbers together

3️⃣ Compare your estimate to the exact answer

Let's Practice Together!

Example 1: School Supplies

Sarah is buying school supplies. The notebook costs $3.75, pencils cost $2.15, and an eraser costs $0.95. About how much will she spend?

Notebook: $3.75 → $4
Pencils: $2.15 → $2
Eraser: $0.95 → $1

Estimated total: $7

Actual total: $6.85

Example 2: Game Points

In a video game, you earned 487 points in level 1 and 324 points in level 2. About how many points did you earn altogether?

Round to the nearest hundred:

487 →

324 →

Estimated total: 800 points

Parent Tips 🌟

  • Make it real: Practice estimating grocery totals or distances during car rides.
  • Estimate first: Encourage your child to estimate before calculating exact answers to develop number sense.
  • Play estimation games: Guess how many candies are in a jar or how many steps to the mailbox.

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