Practice Arithmetic Rules Of Modular Arithmetic (7.4.3) - Lecture

Practise this section

8 questions

Flashcard drill
2 cards from this section. Quick, good the night before a test.
Exercise
6 questions · about 4 min · pass mark 70%. Hints available.
Sign up to start the exercise
Quiz
2 questions · about 1 min · pass mark 70%. Hints available.
Sign up to start the quiz

6 sample questions

Question 1.
What is 18 mod 5?
Show hintHide hint
Find how many times 5 fits into 18, and what’s left over.
Question 2.
Calculate (4 + 6) mod 5.
Show hintHide hint
Add the numbers first, then find the remainder when divided by 5.
3Question 3.
What is 9 mod 4?
- 1
- 2
- 3
Show hintHide hint
Perform the division and find the leftover.
4Question 4.
Is division always defined in modular arithmetic?
- True
- False
Show hintHide hint
Think about how division handles negative or smaller numbers in the modulus.
Question 5.
Using the square-and-multiply algorithm, find 7^23 mod 5.
Show hintHide hint
Convert the exponent to binary first.
Question 6.
Provide a real-world application of modular arithmetic in cryptography.
Show hintHide hint
Think about how encrypting messages requires specific math operations that secure them.

4 more questions in this section. Enroll free to practise them all.