🔢Multiplying by 11: You can easily multiply a number by 11 by adding the digits of the number and placing the sum between them.

🔢Multiplying by teen numbers: To multiply a number by a teen number, multiply the units digit of the teen number by the given number, and add a 0 to the result. Then, multiply the tens digit of the teen number by the given number and add the two results.

🔢Multiplying bigger two-digit numbers: Multiply the units digits of both numbers, then cross-multiply the units digit of the first number with the tens digit of the second number and the tens digit of the first number with the units digit of the second number. Add the two cross-multiplication results and the product of the units digits to get the final answer.