What is the Greatest Common Factor (GCF) of the following pair of numbers? Write the letter of the correct answer on the blank before each number 13.) 7 and 21 14.) 15 and 25 15.) 12 and 18 16.) 28 and 35 A. 7 A. 10 A. 12 A. 5 B. 8 8.5 B. 18 B.6 C. 15 C.6 c. 7​
