Illustration 9
In an examination, 96% of the candidates passed & 50 failed. How many candidates appeared ?
Solution
Let the number of candidates appeared be x
Percentage of those who passed = 96%
Percentage of those who failed = (100 – 96)% = 4 %
Number of failures = 4% of x.
4% of x = 50

Hence, the number of candidates appeared is 1250.

Illustration 10
(i)     Chalk contains calcium, carbon and oxygen in the ratio 10 : 3 : 12, find the % of carbon in chalk.
(ii)     If in a stick of chalk, carbon is 3g, what is the weight of the chalk stick ?

Percentage Application

Percentage, Increase and decrease percentage

Percentage Increase

When comparing the increase in a quantity over a period of time, we first find the difference between the original value and the increased value. We then use this difference to find the relative increase against the original value and express it in terms of percentage. The formula for percentage increase is given by:

Percentage Decrease
When comparing the decrease in a quantity over a period of time, we first find the difference between the original value and the decreased value. We then use this difference to find the relative decrease against the original value and express it in the form of a percentage. The formula for percentage decrease is given by:
Percentage: Marks, Profit and loss- Introduction
Profit and Loss Basic Concepts
Let us learn profit and loss concepts in math. It is well explained in terms of cost price and selling price.
Profit(P)
The amount gained by selling a product with more than its cost price.
Loss(L)
The amount the seller incurs after selling the product less than its cost price is mentioned as a loss.
Cost Price (CP)

The amount paid for a product or commodity to purchase is called a cost price. Also, denoted as CP.
This cost price is further classified into two different categories:

Fixed Cost: The fixed cost is constant, it doesn’t vary under any circumstances
Variable Cost: It could vary depending as per the number of units and other factors

Selling Price (SP)
The amount for which the product is sold is called the Selling Price. It is usually denoted as SP. Also, sometimes called a sale price.
Profit and loss as a percentage
Marked Price Formula (MP)
This is basically labelled by shopkeepers to offer a discount to the customers in such a way that,

Formula for profit and loss percentage

Profit and Loss Formulas

Now let us find the profit formula and loss formula.

The profit or gain is equal to the selling price minus the cost price.

Loss is equal to cost price minus selling price.

The formula for the profit and loss percentage is:

Things you should know about discount

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## Batch List

#### clas 7 math

###### Medha Sharma

Course : CBSE Class 7

Start Date : 03.12.2022

End Date : 18.07.2023

Types of Batch : Classroom

 Subject M T W T F S S Mathematics(7 hours) 11:15 AM 11:15 AM 11:15 AM 11:15 AM 11:15 AM 11:15 AM 11:15 AM