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Front

What is a prime number?

Back

A prime number is a natural number greater than 1 that cannot be formed by multiplying two smaller natural numbers. It has exactly two distinct positive divisors: 1 and itself.

Front

What is a composite number?

Back

A composite number is a natural number greater than 1 that is not prime, meaning it has more than two positive divisors.

Front

What does it mean for a number to be divisible by another number?

Back

A number A is divisible by another number B if there exists an integer C such that A = B * C. In other words, when A is divided by B, the remainder is 0.

Front

What are the divisibility rules for 2?

Back

A number is divisible by 2 if its last digit is even (0, 2, 4, 6, or 8).

Front

What are the divisibility rules for 3?

Back

A number is divisible by 3 if the sum of its digits is divisible by 3.

Front

What are the divisibility rules for 5?

Back

A number is divisible by 5 if its last digit is 0 or 5.

Front

What are the divisibility rules for 6?

Back

A number is divisible by 6 if it is divisible by both 2 and 3.

Front

What are the divisibility rules for 7?

Back

To check if a number is divisible by 7, you can double the last digit, subtract it from the rest of the number, and see if the result is divisible by 7.

Front

What are the divisibility rules for 11?

Back

A number is divisible by 11 if the difference between the sum of the digits in the odd positions and the sum of the digits in the even positions is either 0 or divisible by 11.

Front

What is the difference between even and odd numbers?

Back

Even numbers are integers that are divisible by 2, while odd numbers are integers that are not divisible by 2.