Final answer:
The common denominator for 2/7 and 1/2 is 14, obtained by multiplying the individual denominators since they have no common factors other than 1.
Step-by-step explanation:
To find the common denominator for 2/7 and 1/2, you need to find a number that both 7 and 2 divide into evenly. This would be accomplished by taking the product of the two denominators since they have no common factors other than 1 (7 is prime and 2 is not a multiple of 7). Therefore, the common denominator of the two fractions would be 7 × 2, which is 14. You can then convert each fraction to have this common denominator by finding an equivalent fraction for each that has 14 as its denominator. The fraction 2/7 becomes 4/14 (because 2 × 2 = 4) and 1/2 becomes 7/14 (because 14 / 2 = 7).