✨ Vedic Math Secrets
Multiplication by 11: The Sandwich Trick
👤 Student Info
📖 The Trick
To multiply any 2-digit number by $11$, simply "sandwich" the sum of the digits between the digits themselves!
2
+
5
=
7
$25 \times 11 = 2 \dots (2+5) \dots 5 = 275$ 🥪
📚 Examples
Easy: $42 \times 11$
Step: $4 \dots (4+2) \dots 2 = \mathbf{462}$
Step: $4 \dots (4+2) \dots 2 = \mathbf{462}$
Carry-over: $87 \times 11$
Step: $8+7 = 15$. Put $5$ in middle, add $1$ to $8 \rightarrow \mathbf{957}$
Step: $8+7 = 15$. Put $5$ in middle, add $1$ to $8 \rightarrow \mathbf{957}$
Word Problem:
A box has 11 rows of 13 chocolates. How many total?
Step: $1 \dots (1+3) \dots 3 = \mathbf{143}$
A box has 11 rows of 13 chocolates. How many total?
Step: $1 \dots (1+3) \dots 3 = \mathbf{143}$
✏️ Quick Practice
$34 \times 11 =$
$52 \times 11 =$
$91 \times 11 =$
🎯 Quiz Challenge
Quiz Results
0/10