16.Which of the following numbers is the GCF of 81, 90 and 108
A. 9
B. 18
C. 36
D. 41

17. Which set of numbers between 30 and 50 have 7 as their GCF?
A. 35, 40 and 45
B. 35, 42 and 49
C. 33, 40 and 47
D. 34, 41 and 48

18. Which of the following numbers have 12 as their LCM?
A. 2, 4 and 6
B. 3, 6 and 9
C. 2, 3 and 6
D. 3, 4 and 9

19. The GCF of 12, 18 and 21 is 3. What is their LCM?
A. 144
B. 180
C. 252
D. 210

20. What is the LCM of 4 and 11?
A. 11
B. 22
C. 33
D. 44

21.What is the LCM of 10, 20 and 30？
A. 30
B. 60
C. 120
D. 180

22. What is the LCM of 4, 12 and 24?
A. 4
B. 12
C. 24
D. 48

23. Which of the following has 28 as their LCM?
A. 4, 12, and 16
B. 5, 10, and 15
C. 6, 12, and 18
D. 7, 14 and 28

24. What is the Least Common Multiple of 6, 12 and 16?
A. 24
B. 48
C. 64
D. 72

25. Amber has two pieces of ribbons. One piece is 35 inches long and the other is 28 inches. She wants to cut both pieces into equal length. How long should she cut the ribbons?
A. 2 inches
B. 7 inches
C. 11 inches
D. 15 inches

26. Rianne wants to create a snack bag for the street children. She has 24 bread, 18 apples and 12 pieces of fruit juice. What is the greatest number of snack bags she can make if the items should be equally distributed and without any left over?
A. 2
B. 5
C. 6
D. 12

27. A farmer has three sacks of peanuts weighing 35 kg., 25 kg., and 50 kg. respectively. He repacked the peanuts such that the packs have equal weight and largest weight possible. How many kilograms would each pack of peanuts contain?
A. 5
B. 10
C. 15
D. 20

28. Joshua goes swimming every 7 days and biking every 8 days. He did both kinds of exercises today. How many days from now will he go both swimming and biking again?
A. 14
B. 20
C. 35
D. 56

29. Two neon signs are turned on at the same time. Both signs blink as they are turned on. One sign blinks every 8 seconds. The other sign blinks every 12 seconds. In how many seconds will they blink together?
A. 4
B. 8
C. 12
D. 24

30. Joshua is thinking of a number that is divisible both by 7 and 13. What was the smallest number that Joshua is thinking of?
A. 28
B. 39
C. 72
D. 91​