MULTIPLICATION OF ANY TWO NUMBERS, LIES BETWEEN 11 AND 19

Let me explain this rule by taking examples

13*19 = (13+9)*10 + (3*9) = 220 + 27 = 247
Means add first number and last digit of the second number take zero in the third place of this number then add product of last digit of the two numbers in it

EXAMPLE.

18*14 = (18+4)*10 + (8*4) = 220 + 32 = 252