Math worksheet featuring ten percentage word problems designed to challenge students' understanding of calculating percentages in real-world scenarios.

Problem Analysis and Solution

We will solve each percentage problem step by step and identify any impossible or trick problems.

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#### Problem 1:
- Question: In a class of 30 children, 60% of the children are girls. How many girls are there in the class?
- Solution:
- Total number of children = 30
- Percentage of girls = 60%
- Number of girls = \( 30 \times \frac{60}{100} = 30 \times 0.6 = 18 \)
- Answer: 18 girls

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#### Problem 2:
- Question: In a packet of 40 skittles, 30% are red. How many red skittles are there?
- Solution:
- Total number of skittles = 40
- Percentage of red skittles = 30%
- Number of red skittles = \( 40 \times \frac{30}{100} = 40 \times 0.3 = 12 \)
- Answer: 12 red skittles

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#### Problem 3:
- Question: In a group of 30 children, 80% can swim. How many children can swim?
- Solution:
- Total number of children = 30
- Percentage who can swim = 80%
- Number of children who can swim = \( 30 \times \frac{80}{100} = 30 \times 0.8 = 24 \)
- Answer: 24 children can swim

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#### Problem 4:
- Question: Frazer scores 70% in a spelling test with 20 questions. How many did he get right?
- Solution:
- Total number of questions = 20
- Percentage score = 70%
- Number of correct answers = \( 20 \times \frac{70}{100} = 20 \times 0.7 = 14 \)
- Answer: 14 correct answers

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#### Problem 5:
- Question: Toronto FC have lost 25% of their games. If they have played 16 games, how many have they lost?
- Solution:
- Total number of games played = 16
- Percentage of games lost = 25%
- Number of games lost = \( 16 \times \frac{25}{100} = 16 \times 0.25 = 4 \)
- Answer: 4 games lost

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#### Problem 6:
- Question: In a group of 26 children, 50% have blue eyes. How many children have blue eyes?
- Solution:
- Total number of children = 26
- Percentage with blue eyes = 50%
- Number of children with blue eyes = \( 26 \times \frac{50}{100} = 26 \times 0.5 = 13 \)
- Answer: 13 children have blue eyes

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#### Problem 7:
- Question: 20% of the animals in an animal rescue centre are cats. What percentage are dogs?
- Solution:
- Percentage of cats = 20%
- The question does not provide information about the percentage of dogs or other animals. Without additional information (e.g., the total percentage of all animals or the percentage of dogs specifically), it is impossible to determine the percentage of dogs.
- Answer: Impossible to solve without more information.

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#### Problem 8:
- Question: A toy car costing $50 is reduced by 10% in the sale. How much money is it reduced by?
- Solution:
- Original price of the toy car = $50
- Discount percentage = 10%
- Reduction amount = \( 50 \times \frac{10}{100} = 50 \times 0.1 = 5 \)
- Answer: $5 reduction

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#### Problem 9:
- Question: In a study of 200 students under 25 years old, 20% have not yet learned to drive. How many students cannot drive?
- Solution:
- Total number of students = 200
- Percentage who cannot drive = 20%
- Number of students who cannot drive = \( 200 \times \frac{20}{100} = 200 \times 0.2 = 40 \)
- Answer: 40 students cannot drive

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#### Problem 10:
- Question: In a survey of 300 adults, 10% did not know how to ride a bike. How many people is this?
- Solution:
- Total number of adults surveyed = 300
- Percentage who do not know how to ride a bike = 10%
- Number of adults who do not know how to ride a bike = \( 300 \times \frac{10}{100} = 300 \times 0.1 = 30 \)
- Answer: 30 adults do not know how to ride a bike

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Identifying the Impossible/Trick Problem

- Problem 7 is the impossible/trick problem because it asks for the percentage of dogs but does not provide enough information to determine it. We only know the percentage of cats (20%), and there is no information about the percentage of dogs or other animals.

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Final Answer:

\[
\boxed{7}
\]