Least Common Denominator (LCD) is the least number which all the denominators can divide without remainder. The given denominators are 2, 16 and 8. The least number 2, 16 and 8 will divide without remainder is 16. Therefore, to express the fractions 1/2, 3/12, and 7/8 with an LCD, we multiply both the numerator and the denominator of each of the fractions with a common factor that makes the denominator to be 16. Therefore, 1/2, 3/16 and 7/8 expressed with an LCD are (1 x 8) / (2 x 8), 3/16, (7 x 2) / (8 x 2) = 8/16, 3/16, and 14/16.