# Factors and Coprimes 1 - 3

13. Find the sum of all the co-primes of 144
a. 3456
b. 3168
c. 2276
d. 2256

14. Find the number of ways of writing 60 as a product of two co - primes
a. 1
b. 2
c. 3
d. 4

15. Find the product of all the factors of 50
a. $${50}$$
b. $${50^2}$$
c. $${50^3}$$
d. $${50^4}$$

16. Find the number of odd factors of 5400.
a. 16
b. 3
c. 8
d. 12

17. Find the sum of odd factors of 5400.
a. 956
b. 1156
c. 1200
d. 1240

18. Find the number of even factors of 5400.
a. 30
b. 36
c. 42
d. 46