Welcome to Rounding Hill

Rounding helps us estimate. If you have 38 marbles, it's easier to say you have "about 40." In this lab, we learn which "tens" and "hundreds" are the closest neighbors!

The Rounding Rules

Look at the digit to the RIGHT of your target place:

Example: Round 164 to the nearest 100.
We look at the 6. Since 6 is "5 or more," we round 1 up to 2.
Result: 200

Nearest 10

Round this number:

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You Reached the Top!

You are now a Rounding Expert. You can find the nearest tens and hundreds in your sleep!