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\\November 3, 2023 12:46 PM Surender Prajapati Proof 2 Reader _________________________ Date: ___________________74

Think and Answer
What is 1% of 1%?

EXPRESSING A QUANTITY AS PERCENTAGE OF ANOTHER QUANTITY

To express a quantity or a number as percentage of another quantity or number:
Š write the given quantity as numerator and total quantity as denominator.

Š then, convert the given fraction to percentage.
Note
Example: What per cent is: Both quantities must
(a) 15 min of 5 hours? (b) 350 mL of 5 L? have same unit.

Solution: (a) 15 minutes of 5 hours = 15 minutes of 300 minutes

Fraction formed = 15 1 hour = 60 min
300
15 5 hours = 5 × 60 min
= × 100 % = 5%
300 = 300 min
(b) Given quantity = 350 mL

Total quantity = 5 L = 5000 mL
350 7
Fraction formed = = (Divide by common factor 50)
5000 100
= 7% (Remove 100 from denominator and put a % sign)

REAL LIFE PROBLEMS BASED OF PERCENTAGE

Example 1: Madhu obtained 54 marks out of 75 in a Maths test. Express her marks as per cent.
Solution: Total marks = 75

Marks obtained by Madhu = 54

Per cent marks = 54 18 18 × 100 % = (18 × 4)% = 72%
× 100 % =
7525 25
Thus, Madhu obtained 72% marks in the Maths test.

Example 2: The strength of a school is 1200. If there are 480 girls in the school. What
per cent of girls and boys in the school?

Solution: Total number of students in the school = 1200
Number of girls in the school = 480
Number of boys in the school = 1200 – 480 = 720

480 480
Per cent of the girls in school = × 100 % = % = 40%
1200 12
Now, per cent of boys in the school = 100% – 40% = 60%
Thus, there are 40% girls and 60% boys in the school.

250 Mathematics-5