School Olympiads - International Mathematics Olympiad (IMO)

Number Theory, Advanced Algebra & Olympiad Geometry question bank (Mathematical Reasoning & Achievers Section)

Practice 51 free School Olympiads - International Mathematics Olympiad (IMO) Mathematical Reasoning & Achievers Section - Number Theory, Advanced Algebra & Olympiad Geometry questions with answers and step-by-step solutions.

Q1.

SOF IMO (Number Theory): In 'Number Theory: Primes, Divisibility Rules, Modular Arithmetic and Cryptarithms', what is the remainder when $2^{100}$ is divided by $7$?

(A)

$2$ (Since $2^3 \equiv 1 \pmod 7 \implies (2^3)^{33} \times 2^1 \equiv 1 \times 2 = 2$) (Number Theory: Primes, Divisibility Rules, Modular Arithmetic and Cryptarithms)

(B)

$1$

(C)

$4$

(D)

$0$

Show answer & solution
Verified Answer & Solution Locked
Sign in to your free student account to reveal verified answers, instant hints, and detailed explanations.
Sign in to view
Q2.

Combinatorics & Pigeonhole Principle: In 'Number Theory: Primes, Divisibility Rules, Modular Arithmetic and Cryptarithms', what is the minimum number of socks that must be drawn from a drawer containing 10 blue socks and 10 red socks in the dark to guarantee at least one matching pair?

(A)

3 socks (By Pigeonhole Principle with 2 color categories) (Number Theory: Primes, Divisibility Rules, Modular Arithmetic and Cryptarithms)

(B)

11 socks

(C)

2 socks

(D)

4 socks

Show answer & solution
Verified Answer & Solution Locked
Sign in to your free student account to reveal verified answers, instant hints, and detailed explanations.
Sign in to view
Protected Questions

Unlock All 51 Questions in Number Theory, Advanced Algebra & Olympiad Geometry

Log in or sign up free to access every question with complete solutions, create chapter practice tests, and track your performance.

Sign up free to access all 51 questions

Unlock every Number Theory, Advanced Algebra & Olympiad Geometry question, generate papers, and practice at your own pace.