Number theory puzzles

Divisibility, primes, remainders, and digit problems in the AMC style.

Standards:AMC 8AMC 10

Try it: three questions

Real questions from the practice bank. Tap an answer to check it.

Question 1 of 3

What is the sum of all divisors of 28?

Question 2 of 3

A positive integer n is divisible by 6 and by 8. What is the least possible value of n?

Question 3 of 3

A positive integer n is divisible by 6 and by 8. What is the smallest possible value of n?

How this fits in

Number theory puzzles is one skill in the SAT / Olympiad Prep unit. Students read the unit lesson, then earn a bronze, silver, or gold medal on their last 10 answers. Medals never go down. A mastered unit comes back for review after 1, 3, 7, 16, and 35 days so it stays learned.

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