Modular Arithmetic and Caesar Cipher Quiz

In modular arithmetic, what does a ≡ b (mod n) mean?

• a and b have the same remainder when divided by n

• a and b are equal numbers

• a is always greater than b in mod n

• n divides both a and b equally

In a Caesar cipher with shift 3, what letter does 'D' encrypt to?

• A

• G

• F

• E

Calculate 7×3(mod5)

• 6

• 21

• 1

• 4

Tags

CCSS.7.NS.A.2C

Which property is NOT preserved in modular arithmetic?

• Associative property

• Division property

• Commutative property

• Distributive property

Tags

CCSS.7.NS.A.2C

What is 25+18(mod7)?

• 1

• 6

• 4

• 3

Tags

CCSS.7.EE.B.3

In modular arithmetic, multiplicative inverses exist when:

• The modulus is composite

• The number and modulus are coprime

• The number is larger than the modulus

• The modulus is even

Which shift in a Caesar cipher transforms "HELLO" to "IFMMP"?

• 2

• 0

• 3

• 1

What is −5(mod4)?

• −1

• 3

• −2

• 1

Tags

CCSS.8.EE.A.1

In a Caesar cipher, what happens when you apply a shift of 26?

• The message becomes encrypted

• Nothing changes

• The message becomes reversed

• The shift is invalid

What is 12÷3(mod5)?

• 4

• 2

• 1

• 3