Commercial Maths

Increase and Decrease Percent 

To calculate percentage of increase and decrease we need to use this formulas

Increase % = Actual increase  x 100
Decrease % = Actual decrease  x 100

Example 1. The price of a tablet was ₹22,000 last year. If there is a decrease of 10 %. What is the price of the tablet this year ?

Solution : Price of tablet last year = ₹22,000 

Actual decrease = 10 % of ₹22,000
                           = ₹   10   x  22,000   
                            =  ₹2,200

Price of the tablet this year = ₹(22,000 - 2200) = ₹19,800

Example 2. The population of city increases every year by 10 %. If the Population in the year 2018 is 1,18,800. What was the population in the 2017.

Solution :- Let the population in the year 2017 be 100

Therefore, 2018 population = 100 + 10 = 110 
Population in 2018 2017
Assumed 110 100
Actual 118800 x

Now we will do cross multiplication 
             105 x =  118800 x 100
                   x  =  118800 x 100
                      = 1,08,000

Ans. The population of the city in the year 2017 is 1,08,000.

Profit and Loss
First, for finding the profit and loss, we need to learn this definitions.
Cost Price- It is the price at which an article is purchased. It is denoted by CP.
Selling Price- It is the price at which an article is sold. It is denoted by SP.
Now, we are ready for learning what is Profit.
Profit- If the Selling Price (SP) is more than the Cost price (CP), then the seller earns a gain or a profit.
Now, we are ready for learning what is Loss.
Loss- If the Cost Price (CP) is more than the Selling price (SP), then the seller suffers a loss.

Profit and Loss Sums

Before, we start solving the sums, we have to learn the formulas which are useful in these types of sums.
Profit % = Profit  x 100
Loss % = Loss  x 100
SP         = 100+Profit

CP                100
SP         = 100-Loss
CP                100

Marketed Price and Discount
In every shops, every article which is to be sold has a price written on it. This price which is tagged to it or marked on it is called the marked price. It is denoted by MP.

Discount is always expressed as a percent of the marked price.

Sales Price - Market Price Relationship 

Sale Price = MP  -  Discount
Discount % = Discount  x 100

Goods and Service Tax (GST)
Goods and Service Tax (GST) is a destination based tax on comsumption of goods and service. It has replaced sales tax and VAT.

Simple Interset 
In Simple Interset, the interset on a given amount remains the same every year. In other words, the depositor will earn the same amount of interest every year during the money deposit period.

Simple Interest =  P x R x T

Where P is Principal, R is Rate and T is Time.
time: 0.0146119595