Any pair of prime or relatively prime numbers.
Two numbers are relatively prime if their GCF is 1.
Pick pairs of prime numbers. Pick any pairs of prime numbers.
The GCF of two prime numbers is 1. 4, 9 and 25 are relatively prime.
It means write down three pairs of numbers that are relatively prime like 4 and 9, 5 and 6, 13 and 25
False. Consider 4 and 9. Neither are prime, but they have no common factors other than 1 and are therefore relatively prime. More generally, any two numbers p^n and q^n where p, q both prime and n<>p or q and n>1 are relatively prime. This is by no means all pairs of relatively prime numbers, but it's an easy way to find examples where neither of the pair is prime.
Find their GCF.
An easy way to find a number relatively prime to another number is to find a nearby prime number. For example, 53 is relatively prime with 50. The following pairs are relatively prime. 3, 50 19, 50 37, 50 49, 50 50, 69 50, 201 50, 341 Any number that is not divisible by 2 or 5 will be relatively prime to 50.
You can multiply the number 18 by different numbers that are relatively prime, for example by different prime numbers.
28 If numbers are relatively prime (no common factor other than 1), just multiply them to get the L.C.M. If the are not relatively prime, then decompose them into prime factors, and find the number got by multiplying those exponents.
When 2 numbers have their GCF = 1, it means that the numbers are relatively prime to each other, which doesn't necessarily mean that they are prime on their own. There are 2 cases where relative prime can be guarenteed: All prime numbers are guarenteed to be relatively prime to all other prime numbers. Any prime number is guarenteed to be relatively prime to any composite number smaller than the prime number. If neither of the above 2 conditions are met, manual calculations must be done to find any existing GCF.
The only two consecutive numbers that are both prime are 2 and 3. Since there are no other even prime numbers (other than 2), there are no more pairs of consecutive prime numbers. Therefore, the term "twin primes" usually refers to pairs of prime numbers that are 2 numbers apart. Examples are (3, 5), (5, 7), (11, 13), (101, 103), and many others more. It is not currently know whether there are infinitely many twin primes.