324 × 101 in Seconds? Multiply Any Number by 101 | Mental Math Trick for Kids (Grades 3–6)

Learn to multiply any number by 101 in your head. For 2-digit numbers you just write the number twice. The rule: 101 × a number = the number, then the number again. For 3-digit numbers, shift and add. Example: 27 × 101 = 2727. 85 × 101 = 8585. 3-digit: 324 × 101 = 32400 + 324 = 32724. Chapters 0:00 Welcome back 0:08 The 5-second challenge: 101 × 64 0:33 The rule 0:38 Example: 27 × 101 0:57 Your turn: 85 × 101 1:12 What about 3-digit numbers? 1:22 Level up: 324 × 101 1:54 Boss level: 648 × 101 (with a carry) 2:31 Your challenge: 72 × 101 and 512 × 101 2:42 What's next Practice (answers in the pinned comment) 72 × 101 39 × 101 86 × 101 512 × 101 245 × 101 Previous trick: Multiply by 11 →    • Multiply Any Number by 11 in 2 Seconds | M...   Next trick: Multiply numbers close to 100 →    • 93 × 96 in 5 Seconds? Multiply Numbers Nea...   All tricks in order → [playlist link] Math Sigmas is a weekly mental math channel for kids in grades 2–6, and for anyone training for Math League, Number Sense or MOEMS. New trick every week. #mentalmath #mathtricks #multiplication #mathforkids