Percentage | Formulas | Problems

What is Percentage?

A fraction that has 100 in the denominator is known as Percentage. The sign of percent resembles like symbol “ %” and it also represents with an abbreviation like “pct” or “pc”. A percentage is also referred to as the pure number or Dimensionless number.

Example: –

A number after symbol, like 30% is known as “Thirty percent”. If it will be written in fraction then the same 30% will be written as 30/100 or 3/10 and in Decimal it will be written as 0.3.

Percentage Formula

For finding the percentage for any value, you have to divide the given quantity to total amount and multiplied the value by 100 from the value you got by diving the given quantity to total amount.

P = XN x 100

X = given quantity
n = total amount
P = percentage of quality

Example:If only 10 of the 100 balls were bad, what percent is that?
P = XN x 100
X = 10
n = 100
According to percentage formula
P = 10/100 x 100
= .1 x 100
= 10%

Change in percentage

Change in the percentage means the change comes in the percentage of any value after increasing or decreasing its value.

% change = (new value – old value)original value x 100

Example: The price of some apples is increased from 48p to 67p. By how much percent has the price increased by?
% change = (new value – old value)original value x 100
= (67 – 48)48 x 100
= 39.58%

Percentage error

A percentage error is used to find the percent of the error in any value. To find the percentage error we subtract the measured value from its original value and multiply by 100 from the value came by the subtracting measured and original value. Then we divide the value we obtain from the original value and then the value comes in last after dividing by original value is the percent error.

% error = (original value – measured value)original value x 100

Original value

Original value = new value100 + %change x 100

Percent Increase and Decrease

Percent increase or decrease is known as the change in the value of percentage that is decreased or increased with its original value. It is used to derive the percentage of profit and the loss.

Percentage Increase = Increase in valueoriginal value x 100

Percentage Decrease = Decrease in valueoriginal value x 100

Example: The price of rice is increased from $10 to $12.50 per kg. Find the percentage increase in price.

Price of rice before = $10
Price of rice now = $12.50
Increase in price = current price – original price
= $12.50 – $10
= $2.50
Therefore, percentage increase in price = Increase in price/Original price × 100 %
= 2.50/10 × 100 %
= 250/10 %
= 25 %
Thus, increase in price= 25 %

Example: The cost of an article is decreased by 15%. If the original cost is $80, find the decrease cost.
Original cost = $80
Decrease in it = 15% of $80
= 15/100 × 80
= 1200/100
= $12
Therefore, decrease cost = $80 – $12 = $68

What is CGPA?

The grade pointing system in the education sector is called the CGPA.
Example: –

I hope, this article will help you a lot to understand the Percentage | Formulas | Problems. If you still have any doubts and problems with any topic of mathematics you can ask your problem in the Ask Question section. You will get a reply shortly.

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