posted by .

Find the least common multiple in each set of numbers.

1) 8,9,12,18
2) 6,8,9,27,36

I have trouble factoring the denominators in this one.

3/7 + 2/5 + 1/10

try a lcd of 70

The LCM is that smallest whole number that each of your given numbers divide into
8 = 2x2x2
9 = 3x3
12 = 2x2x3
18 = 2x3x3

so looking at those, I will need three 2' and two 3's
LCM = 2x2x2x3x3 = 72

7 = 1x7
5 = 1x5
10 = 2x5

So your lowest common denominator, or the LCM, is
7x5x2 = 70

I need to rewrite the fractions so that all the denominators are the same.

## Similar Questions

1. ### math

what is the least common denominator? It is the smallest number into which all of the denominators in a series of fractions can be evenly divided. For instance, is you have fractions 1/2, 2/3 and 5/6, the denominators are 2, 3 and
2. ### algebra !

i need help on adding and subtacting rational numbers like -7over12+5 over 6 When adding rational numbers we need a common denominator. We have -7/12 + 5/6 What is the least common multiple of 12 and 6?
3. ### MATH

HOW DO LEAST COMMON MULTIPLES WORK. IT SAYS THERE IS A PROBLEM TO SOLVE BUT MY MOM AND I CAN'T FIND IT. THEY CIRCLED BOTH 2'S AND 3'S. The least common multiple of 2 and 3 is six. The least common multiple of 12 and 6 is 12. # noun: …
4. ### math

5/10+12/16+(15/20-4/16) Well you need to solve in the parentheses first, by making them common denominators. (15/20 - 4/16)=(60/80 - 20/80) Then subtract. (40/80) then simplify. (1/2) Next make all the fractions with common denominators. …
5. ### math

how do I find the numerators when I have 2 fractions with unlike denominators and the simplified answer you get when adding them?
6. ### math

adding fractions with unlike denominators: 7/9 + 5/6?
7. ### math

in what way is subtracting fractions with unlike denominators like adding fractions with unlike denominators?
8. ### fractions with unlike denominators

What is a easy way to add or subbtract fractions with unlike denominators
9. ### math

adding and subtracting fractions with unlike denominators
10. ### Math

Find three pairs of numbers for which the LCM (least common multiple) is the product of the two numbers; The pairs and LCMs are: 8 and 12: 24; 3 and 15: 15; 7 and 11: 77; 9 and 10: 90; 24 and 36: 72; 20 and 25: 100; 14 and 42: 42; …

More Similar Questions