No.
54/206 =27/103 I divided the numerator and denominator by two.
54 is.
54
54
It's 42/54
864
LCD(54, 24) = 216
It is 54
54
54
54^14 = 1,792,720,717,930,698,493,280,256
You can find a common denominator of any set of denominators by multiplying them together. That result will not necessarily be the lowest common denominator. Example: 1/6 and 1/9 6 x 9 = 54 and 54 is a common denominator of 6 and 9, but the LCD is 18.