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15 is 10 + 5, and 5 is half of 10. So multiply by 10 (just add a 0), then add half of that answer. Two tiny steps instead of a long multiplication.
✓ You passed this lesson’s test.
Ten and half again — “× 15 = × 10, plus half of that”
Use it for: Quarter hours (15 minutes), 15% tips and discounts, and the table of 15.
Check: 46 × 15 = 46 × 3 × 5 = 138 × 5 = 690 ✓
▶ Watch it animated✓ Written and checked by the TalentJR team · Updated 13 Oct 2026 · How we make our lessons
Work it out in your head or on paper, then tap your answer — or type it and press Check. Stuck? Press “Show me how”.
Right: 0 · Tried: 0
20 questions. Check each answer, then go to the next one. Get 16 or more right to pass — and beat the clock: finish within 3 min.
🏅 Sign in with Google to earn the ⏰ Quarter-Hour Ace badge when you pass — and a certificate when you finish all 5 lessons of Part 2 · Speed multiplying. You can still take the test without signing in.
Why does it work? When should you use it? Ask in English, मराठी or हिंदी.
Sign in with Google to ask Free — 20 questions a day.
Prefer a real teacher? TalentJR teachers take live online classes anywhere in India. Tell us what you need and our team will call you with timings and fees.