1. a b 0 Let a b be an unknown two digit number. a is in 10’s position and b is in 1’s position a b  1 1 a b a a+b b Multiplication of a two-digit number  11 +

2. + a b 0 a b  1 1 a b a a+b b a b ba+ba Paper & pencilMental math

3. Multiplication of a two-digit number  11 a b ba+ba Mental math 6 2  11 = 6 8 2

4. Multiplication of a two-digit number  11 a b ba+ba Mental math 6 2  11 = 682 3 9  11 = 1212 93

5. Multiplication of a two-digit number  11 a b ba+ba Mental math 6 2  11 = 682 3 9  11 = 3 9 12 4 2 9

6. Multiplication of a two-digit number  11 a b ba+ba Mental math 6 2  11 = 682 3 9  11 = 429