Question

What is the LCD of 3/10 and -4/15 ?

Answer 1

The lowest common denominator is the smallest number that 10 and 15 can get into.

first you have to list the first 10 multiples of 10

10,20,30,40,50,60,70,80,90,100

and then the first ten multiples of 15

15, 30, 45, 60, 75, 90, 105, 120, 135

The smallest number that both of them have is 30 so that's the Lowest Common Denominator

Answer 2

The least common denominator is the smallest number that 10 and 15 can get into.

List the multiples:

10:

10, 20, 30, 40, 50, 60, 70, 80, 90, 100

15:

15, 30, 45, 60, 75, 90, 105, 120, 135

The smallest number that both of them have is 30, so that's the LCD.