More Factors and Multiples-

-The Greatest Common Factor

TEK 6.1E Objective 1

Post Test Questions

1. Which of these is the best definition for the greatest common factor of two numbers?
a. The largest number that goes into each only once.
b. The smallest number that will go into the larger of the two numbers given.
c. The dividend of the larger number of the two.
d. The largest number that is a factor of both of them.

2. Which of these explains how to find the greatest common factor of two numbers?
a. List the factors of both numbers and find which of them are the same and select the largest
b. Find the prime factorizations of both numbers and multiply together the factors that they both have in common
c. Both of these
d. Neither of these

3. Finish this diagram to find the prime factorization of 84. Which is it?

a. 25 X 5
b. 5 X 2 X 7 X 3
c. 5 X 5 X 5 X 3
d. 7 X 3 X 2 X 2

4. After figuring the prime factorizations of two numbers, the next step is to
a. Divide the largest factor by the smallest factor if they are in common
b. Multiply all of the factors which they do not have in common
c. Multiply the greatest factors
d. Multiply all of the factors which they have in common

5. The prime factors of 16 are 2 X 2 X 2 X 2 and the prime factors of 24 are 2 X 2 X 2 X 3. What is the greatest common factor?
a. 8
b. 9
c. 6
d. 3

6. The greatest common factor of 57 and 78 is-
a. 4
b. 3
c. 13
d. 19

7. The greatest common factor of 24 and 36 is-
a. 4
b. 8
c. 12
d. 16

8. The greatest common factor of 28 and 54 is
a. 2
b. 3
c. 9
d. 13

9. The greatest common factor of 80 and 99 is
a. 11
b. 3
c. 5
d. None of these

10. The Jones family and the Hawkins family both bought the exact same Halloween candy packages at the same store. If the Hawkins family has 140 candies and the Jones family has 252 candies, what is the largest amount of candy that could have been in each package?
a. 16
b. 24
c. 28
d. 36