Which of the following is a composite number? a. 31 b. 49 c. 73 d. 109 Which pair of numbers is relatively prime? a. 20 and 76 b. 25 and 65 c. 46 and 87 d. 63 and 117
d. 109 is a composite number and c. 46 and 87 are relatively prime
31 can not be divided by any other number other than itself and 1. So it is not a composite number. Same as 73. Same as 109. So only 49 is a composite number. C. The relative prime is when between two numbers the only common factor is 1. Option C 46 and 87 is the relative prime, because only 1 is the common factor between them. Other pairs do not show this property, either they have a common factor other than 1, such as 2, 3, or 5.