5
least common denominator of 26 42 and 28 is 1092.
26
A common denominator, though not the least one, is 26*8 = 208.
A common denominator, though not the least, is 5616.
2
Their product.
156
286
There is none because the Least Common Denominator (or LCD) is the Least Common Multiple (LCM) of the denominators of two or more fractions.
LCD(3, 26) = 78
The least common denominator (LCD) is 1.