Question

11

Which statement is true?
A
The greatest common factor of 10 and 14 is 5.
B
The greatest common factor of 10 and 15 is 5.
The greatest common factor of 13 and 21 is 3.
The greatest common factor of 14 and 21 is 3.
D

Answer 1

B.

Explanation:

We can find the GCF by considering the prime factors:

GCF of 5 and 15:

5 = 5

15 = 3* 5

5 is common to both sets of factors so 5 is the GCF.

Only B is true.

For example consider D, 14 and 21

14 = 2 * 7

21 = 3 * 7

The GCF is 7 ( NOT 3).

A:

10 = 2 * 5

14 = 2 * 7

The GCF is 2 (NOT 5)

C.

13 and 21:

13 = 13

21 = 3 * 7

There are no common factors here so it is NOT 3!!

Answer 2

The answer is B, I hope this helps!