Maths: Tricks

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

Simple Formulas related to Polygons and Angle Conversion

Conversion of Angles

Converting Angle in Degree From Radian

Angle A radian to Degree:

A rad = A*(180/pie) degree