If that's 5/12, 10/13 and 7/9, the LCD is 468.
all of the LCDs of 10 are in 20, so 10 is useless. There are no common factors in 20 and 13, so the way to get it is 20 x 13 = 260
LCD(40, 50) = 200
Write the multiples of each: 5, 10, 15, 20 10, 20, 30, 40 10 is in each, so it is the answer.
20
The LCD of 5 and 4 is 20.
The least common multiple of 13 and 20 is 260.
20
260
LCD(10, 20) = 20
20
Lcd of 5,4,2 is 20 because 5*4=20 and 2*10=20
20
240
LCD(40, 50) = 200
Pairs of number with the LCD of 5 are 5 and 10, 10 and 15, 20 and 25, and many more.
Write the multiples of each: 5, 10, 15, 20 10, 20, 30, 40 10 is in each, so it is the answer.
20
LCD(12, 20) = 60