To calculate a number when its percentage is known are discussed here. Let us consider some of the examples on word problems on percentage.
1. Marlena scored 80% out of a total of 500 marks. How many marks did he score?
Solution:
Marlena’s marks = 80% of 500
= (80/100) × 500
= (4/5) × 500
= (4 × 500)/5
= 2000/5
= 400
Therefore, Marlena scored 400 marks.
2. In an examination, Sherry scored 89% marks out of 750 marks. How many marks did he get?
Solution:
Sherry’s marks = 89% of 750
= (89/100) × 750
= (89× 750)/100
= 66750/100 ÷ 50/50
= 1335/2
= 667.5
Therefore, Sherry scored 667.5 marks.
These are the word problems where we need to calculate a number when its percentage is known.
1. Sara got 150 questions as assignment for a week. If she did 70% of the questions in the first four days, how many questions would she have to do in the remaining days?
Solution:
Questions completed by Sara in the first 4 days = 70% of 150
= (70/100) × 150
= (7 × 150)/10
= 1050/10
= 105
Total questions = 150
Question completed = 105
Remaining questions = 150 – 105
= 45
Therefore, Sara would have to do 45 questions in the remaining days.
2. On a rainy day 35% of a class of 40 students were present. Find the number of absentees.
Solution:
Number of students present on a rainy day = 35% of 40
= (35/100) × 40
= (7/20) × 40
= (7 × 40)/20
= 280/20
= 14
Total numbers students = 40
Number of students were present on a rainy day = 14
Number of students were absentees on a rainy day = 40 – 14
= 26
Therefore, 26 students were absent.
3. Paul earns $ 24000 per month. He saves 28% of his salary. How much does he spend every month?
Solution:
Paul earn per month = $24000
Amount of money he save from his salary = 28% of 24000
= (28/100) × 24000
= (7/25) × 24000
= (7 × 24000)/25
= 168000/25
= 6720
Paul saved from his salary = $6720
Paul spend = $(24000 – 6720) = $17280
Therefore, Paul spend $17280 from his salary.
4. The population of a village is 2400. If 12% were children, find the number of adults.
Solution:
Total population in a village = 2400
Population of children in a village = 12% of 2400
= (12/100) × 2400
= (3/25) × 2400
= (3 × 2400)/25
= 7200/25
= 288
Population of adults = 2400 – 288
= 2112
Therefore, there are 2112 number of adults.
These are the different types of word problems to calculate a number when its percentage is known.
To Convert a Percentage into a Fraction
To Convert a Fraction into a Percentage
To find the percent of a given number
To find what Per cent is one Number of another Number
To Calculate a Number when its Percentage is Known
5th Grade Numbers Page
5th Grade Math Problems
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