Maths Formula

income = expenditure + saving
if a,b is given number so third proportional to a and b is = b²/a
if a,b,c is given number so fourth propotional to a,b,c = (b⨯c)/a
simple interest (SI) = PRT / 100
area of walls = 2 h (l+b) [h=height, l=length, b=breadth] unit in sq.m
speed = distance / time
speed of boatman = (speed of upstream + speed of downstream) / 2
average speed = total distance / total time
if some fraction are given so HCF of fractions = HCF of nemerators / LCM of denominators
profit = sp - cp [cp=cost price, sp=selling price]
profit % = (profit / cp) ⨯ 100
area of trapezium = 1/2 ⨯ sum of parallel sides ⨯ height
volume of cylinder = πr²h
total surface area of cylinder = 2πr(r+h)
a^m ⨯ aⁿ = a^m+n
(x)^1/2 is same to √x Example. (4)^1/2 = √4 = 2