Prime and Composite Numbers Concepts

The video tutorial explains how to write a program to test if a number is prime or composite. It begins by defining prime and composite numbers, then guides the viewer through setting up a program that prompts user input, optimizes a loop to check for factors, and implements a divisibility test. The program displays whether a number is composite and stops further checks if a factor is found. If no factors are found, it displays that the number is prime. The tutorial concludes with testing examples and a reminder to avoid large numbers due to processing time.

What is a prime number?

• A number divisible by two and itself only

• A number divisible by any number

• A number that is a multiple of two numbers

• A number divisible by one and itself only

What is a composite number?

• A number divisible by one and itself only

• A number that is a multiple of two numbers other than one and itself

• A number that cannot be divided

• A number that is a prime

What is the first step in the primality testing program?

• Display the result

• Prompt the user to enter a number

• Start a loop from one

• End the program

Why do we start the loop from 2 instead of 1?

• Because 1 is not a factor

• Because every number is divisible by 1

• Because 1 is a composite number

• Because 2 is the smallest prime number

Why do we only check up to half of the number in the loop?

• Because factors repeat after halfway

• To avoid errors in calculation

• To save time and resources

• Because the second half is always composite

What is the purpose of the 'not' logic in the if statement?

• To confirm the number is prime

• To invert the result of the divisibility test

• To skip the loop

• To end the program

What happens if the fraction part of n/a is zero?

• The program ends

• The number is composite

• The number is prime

• The loop continues

What should the program do if a number is found to be composite?

• Continue the loop

• Display 'composite' and stop

• Display 'prime' and continue

• Restart the program

What is displayed if the number passes through the loop without being composite?

• Nothing

• Composite

• Error

• Prime

What is the result of testing the number 743?

• Unknown

• Prime

• Composite

• Error