210
90
LCD(7, 5, 10) = 10
the answer is 45. You compute it by reducing each number to its prime factors, and taking the unique set. 9 factors to 3x3, 15 to 3x5, so the unique set is one 3 from the 9, one 3 that they share and one 5 from the 15. 3x3x5=45. Of course, 135 is also a common denominator but isn't the least. you can always find a CD by multiplying the two. The LCD will make simplification after the addition or subtraction of fractions much easier.
245
The lcd is the lowest common multiple (lcm) of 10 and 45 which is 90.
LCD(9, 15) = 45
210
45
45
495
It is: 585
90
The LCD of 0.9 (9/10) and 1/45 is 90.
gcf of 45 and 75 is 15.
90
2205