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Decimal Calculator

Choose a fast answer or optional teaching.

Practice Mode

Try the problem first. Ace gives one hint at a time.

4.8 + 2.35 = ?

⚡ Decimal Shortcut Vault

×10, ×100, ×1000

Each multiplication makes every digit worth 10, 100, or 1000 times as much. The decimal point appears to shift right relative to the digits.

÷10, ÷100, ÷1000

Each division makes every digit worth one-tenth, one-hundredth, or one-thousandth as much.

Friendly numbers

9.9 + 4.6 → think 10 + 4.6 − 0.1 = 14.5.

Important: ACELZO teaches place value, not the misleading rule “just move the decimal.” The digits change place value.

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