Easy prime number question. Need help or answer

Algebra
Tutor: None Selected Time limit: 1 Day

How many natural numbers between 43 and 274 are relatively prime to 15? And how could you determine how many natural numbers were relatively prime to 15 between any pair of natural numbers, a and b?

Jun 1st, 2015

There are 230 natural numbers between 43 and 274 (I assumed this to mean not inclusive). 77 are divisible by 3, 46 are divisible by 5, but 18 are divisible by both 3 and 5. 230 - 77 - 46 + 18 = 125. If you assume INCLUSIVE of 43 and 274, both are relatively prime to 15, so it would be 127.

Jun 1st, 2015

Thanks, but I need to know how this result was found.

Jun 3rd, 2015

Did you know? You can earn $20 for every friend you invite to Studypool!
Click here to
Refer a Friend
...
Jun 1st, 2015
...
Jun 1st, 2015
Feb 22nd, 2017
check_circle
Mark as Final Answer
check_circle
Unmark as Final Answer
check_circle
Final Answer

Secure Information

Content will be erased after question is completed.

check_circle
Final Answer