Part A: First, list multiples for each number. The multiples of 5 are: 5, 10, 15, 20, 25 30, 35, 40, 45, 50, 55, 60, etc. The multiples of 12 are: 12, 24, 36,48, 60, etc. The least common multiple is the first common multiple between the two, in this case being 60. The LCM of 5 and 12 is 60.
Part B: SImilar to above, list all factors for each number. 72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, and 72. 81: 1, 3, 9, 27, and 81. The greatest common factor is the highest common number, 9 in this case. The GCF of 72 and 81 is 9.
Part C: To rewrite, we need to take out the 9 by dividing. 72/9 is 8. 81/9 is 9. Therefore, we would get 9(8+9), to equal 153. Your answer here is 9( 8 + 9 ). Hope this helped!
The best way to answer this question is to set up the first sentence as a ratio of large bandages to total bandages. You would write 5 large bandages to 7 total bandages to 7 total bandages. Then you would make this equivalent to x number of large bandages to 60 total. It would look like this 5:7 = x:60. You could use cross products to multiply 60 by 5 to get 300. 7 times x also should equal 300. Unfortunately, this example will not leave us with a whole number of bandages, but 300/7 is a repeating decimal or a mixed number (42 6/7 large bandages).