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
As to your second one,
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.
Answer this Question
algebra ! - i need hepl on adding and subtacting rational numbers like -7over12+...
math - in what way is subtracting fractions with unlike denominators like adding...
MATH - HOW DO LEAST COMMON MULTIPLES WORK. IT SAYS THERE IS A PROBLEM TO SOLVE ...
Math - Find three pairs of numbers for which the LCM (least common multiple) is ...
math - what is the least common denominator? It is the smallest number into ...
math - how do I find the numerators when I have 2 fractions with unlike ...
fractions with unlike denominators - What is a easy way to add or subbtract ...
math - adding fractions with unlike denominators: 7/9 + 5/6?
math - 5/10+12/16+(15/20-4/16) Well you need to solve in the parentheses first, ...
math - adding and subtracting fractions with unlike denominators