Discount, True Discount and Successive Discount Detail, Formulas and Mock Test:

Discount is the reduction given on the Marked Price.
Selling Price (S.P.) is the price payable after reducing the Discount from the Marked Price (M.P.).
Discount = Marked Price – Selling Price
Selling Price = Marked Price – Discount
Marked Price = Selling Price + Discount
Two successive discounts of m% and n% on the listed price < (m + n)% of the listed price, then

Sale price after first discount of m% = List price ×[1- m/100]

Sale price after two discounts of m% and n% = List price [1- m/100][1- n/100]

If m% and n% are two consecutive discounts on a scale, then the equivalent single discount will be;

Discount = [m+n-(m×n)/100]%

If m%, n% and p% be three consecutive discounts, then the single equivalent discount will be;

Discount = [[100 –  (100 –  m)(100 – n)(100 –  p) ]/[100  × 100] ]%

P = (100/((100 – Discount %) ))× S.P.
P. = (((100 –  Discount %))/100)× M.P
Discount Percent = (Discount/(M.P.))× 100
Present worth = (Amount/((100 + (R ×T)) ))× 100 =((True Discount)/((R × T) ))× 100
True Discount = Amount –Present Worth
True Discount = (((Present worth ×  R ×  T))/100)  = ((Amount  ×  (R × T))/((100 +  (R × T)) ))
Sum = [((Simple Intrest ×  True Discount))/((Simple Interest –  True Discount) )]
Simple Interest – True Discount = Simple Interest on True Discount
When the sum is put at compound interest, then Present worth = (Amount/(1 + (R/100) )^T )