Power PlayClass 8 Mathematics Case Study Questions
10 Questions
Generated by KedovoAI
Case 1 of 10
Case Study7 marks
The Impossible Paper Fold
In a science class, students explore the concept of exponential growth by folding a sheet of paper. They start with a standard A4 sheet, which has a thickness of approximately mm, or meters. The students are told that it is physically impossible to fold a piece of paper more than 7 or 8 times. However, they are asked to imagine a magical sheet of paper that can be folded as many times as they wish. With each fold, the thickness of the paper doubles. The class decides to calculate how thick the paper would become after a certain number of folds and compare it to real-world objects. They are curious to see how quickly the thickness grows from something barely visible to astronomical heights.
Questions on this case
1(1 mark)MCQ
What is the thickness of the paper in meters after 3 folds?
2(1 mark)
Write a general expression for the thickness of the paper in meters after 'n' folds.
3(1 mark)MCQ
After 10 folds, the thickness is m. After 17 folds, the thickness is approximately m. How many times thicker is the paper after 17 folds compared to after 10 folds?
4(2 marks)
The height of the Burj Khalifa is approximately 830 m. The students know that . Approximately how many folds would be needed for the paper's thickness to exceed the height of the Burj Khalifa?
5(2 marks)
The distance to the moon is approximately m. Using the approximation , find the approximate number of folds needed to reach the moon.
Case Study7 marks
Digital Lock Security
Estu and Roxie are learning about digital security. They discover that the strength of a password depends on its length and the variety of characters used. They analyze two types of locks. The first is a simple numeric lock that uses a 5-digit password, where each digit can be any number from 0 to 9. The second is an alphanumeric lock that uses a 4-character password, where each character can be any of the 26 uppercase letters (A-Z) or any of the 10 digits (0-9). They want to use exponents to represent the total number of possible passwords for each lock and compare their security.
Questions on this case
1(1 mark)MCQ
How many possible passwords are there for a 2-digit numeric lock (digits 0-9)?
2(1 mark)
Express the total number of possible passwords for the 5-digit numeric lock in exponential form.
3(1 mark)
How many total character options are available for each position in the alphanumeric lock?
4(2 marks)MCQ
Which expression represents the total number of possible passwords for the 4-character alphanumeric lock?
5(2 marks)
Which lock is more secure, the 5-digit numeric lock or the 4-character alphanumeric lock? Justify your answer by comparing the total number of combinations.
Case Study7 marks
Journey Through the Solar System
A science documentary presents fascinating facts about our solar system. It uses scientific notation to express vast distances. The average distance from the Sun to Earth is approximately meters. The distance from the Sun to Saturn is about meters. Light travels at a constant speed of approximately meters per second. Students are asked to use these figures to compare distances and calculate travel times for light, applying their knowledge of exponents and scientific notation. This helps them appreciate the immense scale of space and the utility of scientific notation in handling such large numbers.
Questions on this case
1(1 mark)MCQ
Which of the two planets mentioned, Earth or Saturn, is farther from the Sun?
2(1 mark)
Write the distance from the Sun to Earth in standard form (as a regular number).
3(2 marks)MCQ
Approximately how many times farther is Saturn from the Sun than Earth is?
4(1 mark)
Calculate the time it takes for light to travel from the Sun to Earth. Express your answer in seconds.
5(2 marks)
Find the approximate distance between the orbits of Earth and Saturn, assuming they are aligned on the same side of the Sun. Express the answer in scientific notation.