What This Drill Trains
Multiplying by 10, 100, or 1000 is really about place value: each factor of ten shifts digits one place left. Once that shift feels obvious, metric conversions, percentage shortcuts (×10 then adjust), and large mental estimates become far easier. This drill locks in the pattern before you layer on harder multipliers.
How to Think During the Round
Count the zeros in the power of ten and append that many zeros to the other factor (for whole numbers). ×10 → one zero, ×100 → two zeros, ×1000 → three zeros. Keep the original digits in order — you are shifting, not rearranging. If a problem feels uncertain, say the place-value sentence: “47 × 100 means 47 hundreds.”
You have 60 seconds. Accuracy still outranks raw speed: one calm method repeated well beats a streak of guesses. After the timer ends, notice which problems felt sticky — that short review is where real improvement happens.
Worked Examples
Study these before you press Start. Try to recreate the thinking without looking at the answer first.
36 × 10
Thinking: Append one zero → 360. Digits shift one place left.
Answer: 360
25 × 100
Thinking: Append two zeros → 2500.
Answer: 2500
8 × 1000
Thinking: Append three zeros → 8000.
Answer: 8000
Common Mistakes
- Adding the wrong number of zeros (especially mixing ×100 and ×1000).
- Inserting zeros in the middle of the digits instead of at the end.
- Confusing multiplying by powers of ten with adding powers of ten.
Practice Tips
- Tap a finger for each zero you need to append before typing.
- Read the multiplier aloud as “ten / hundred / thousand” to slow impulsive guesses.
- Connect this skill to percentages: 10% is ÷10; 100% is the whole — related place-value ideas.
Suggested Session Plan
- Read the method section once if this skill is new.
- Cover the answers and re-solve the three worked examples aloud.
- Start the timed round and stick to one strategy.
- Replay once, then write down any fact or pattern you missed.
- If the same error repeats, open the full lesson for more examples and a practice set with an answer key.
Full explanation, extra worked examples, and practice problems for this skill: open the related stage lesson .
Prefer a structured curriculum instead of random drills? Browse all learning stages or read the complete mental arithmetic guide . More timed drills live on the games hub.