Math · Stage 5
Multiply and divide by 10, 100 and 1000 mentally
No pencil needed — just slide every digit along the place-value columns. Count the zeros to know how many places, and which way to shift.
✦ Math📘 Stage 5 · S5⏱ ~11 min🧒 Ages 9–10★ Free to start
I can multiply and divide whole numbers and decimals by 10, 100 and 1000 mentally by shifting every digit along the place-value columns.
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Kavi's No-Pencil Market ⚡
At the night market a customer buys 100 star-cookies at 3.6 coins each. Kavi never reaches for a pencil! "× 100 just slides every digit two places to the left — 3.6 becomes 360," Kavi hoots. The digits travel along the place-value columns; the decimal point stays still.
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What your child will learn
1Each column is ten times its neighbourEvery digit lives in a place-value column. Walk left and each column is worth ten times the one before it: ones → tens → hundreds. Build 6 ones, then tap + on the 10s and 100s to feel each ×10 jump along the columns.
2× 10, × 100, × 1000 → slide LEFTMultiplying makes a number bigger, so every digit slides left. Count the zeros: ×10 = 1 place, ×100 = 2 places, ×1000 = 3 places. The decimal point stays put — it is the digits that move. Tap a row.
3÷ 10, ÷ 100, ÷ 1000 → slide RIGHTDividing makes a number smaller, so every digit slides right — the opposite way. Count the zeros again for how many places. Tap a row to see the shift.
4Judge an answer in one glanceBecause ×/÷ only shift digits, you can check any answer by counting places. If the shift does not match the zeros, the answer is wrong. Tap a row.
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A peek inside
Multiply 3.6 × 100 mentally.
×100 shifts every digit TWO places left: 3.6 → 360
Try this at home: Multiply by 10: 6 × 10 = __ · 34 × 10 = __ · 0.7 × 10 = __
Ready to play and learn?
Start the free interactive lesson, or print the handout for screen-free play.
Part of Math · Stage 5 · S5 on KAVI Academy — a secular, whole-child learning platform for ages 5–12.