What is the common denominator for 1/2 and 1/4

Hi there, 

Common denominator indicates that both denominators (2 and 4) 

Would have a common number when they are factored. 

the factors of 2 are : 1 , 2 , 4 , 6
The factors of 4 are : 1 , 2,  4

Since they asked for a common denominator (in which you can transform one of the denominators into the other's by multiplying it by a specific number)
Then the common denominator would be 4

If you are confused let me know, i can provide you with explanation. 

4 you multiply 2 times two to get four as your denominator so it would be 2/4 &1/4

In general form, you have anumber such as 23. In standard form, since 2 is in the tens place, it is basically 20, and 3 is in the ones place, so it is 3. So you would do (2*10^1) [to get 20] + (3*10^0) [to get 3].

Step-by-step explanation:

I hope that explanation helps.