where, v = speed per hour
t = total time.
(4) Related to pipe and water tank :
Amount of water in a tank at a definite time, Q(t) Qorqt
where, Qo= amount of stored water in a tank at the time of opening the pipe
q = amount of water flowing in or flowing out by the pipe in a unit
time.
t = time taken.
Q(t) amount of water in the tank in time t(+ sign, at the time o f
flowing of water in and – sign, at the time of flowing of water
out are to be used).
(5) Related to percentage :
p br,
where, b = total quantity
r = (rate of) percentage by fraction %
100s
sp = (rate of) percentage by parts = s% of b
(6) Related to profit and loss :
S C(Irr) ;
in case of profit, S C(Ir)
in case of loss, S C(Ir)
where, S (Tk.) = selling price
C (Tk.) = cost price
I = profit
r = rate of profit or loss
(7) Related to investment and profit :
In the case of simple profit,
I = Pnr (taka)
A PI PPnr P( 1 nr) (taka)
In the case of compound profit,
A P( 1 r)n
where, I = profit after time n
n = specific time
P = principal