Finding the prime factorizations of the denominators will help you find the least common denominator. Converting to equivalent fractions with like denominators will allow you to subtract them successfully.
3 x 5 = 15 3 x 7 = 21 3 x 5 x 7 = 105, the LCM
It is the same as finding the LCM of two numbers that have been expressed as a product of their prime factors except that you need to use the highest index for each prime factor.
270000 = 27 x 10000 27 = 3 x 3 x 3 10000 = 10^4 = 2^4 x 5^4 The prime factorization of 270000 = 2^4 x 3^3 x 5^4
That's a false statement. Both 16 and 64 have one prime factor. 16 can't be the LCM of two prime numbers and 64 can't be the product. If you leave out the word prime, you can use 16 and 4.
a and b have no common prime factors. Their LCM is their product.
To simplify fractions, it is necessary to divide the numerator and the denominator by their GCF. You can find their GCF by comparing their prime factorizations. You can find their prime factorizations through the use of factor trees.
Prime factors are part of prime factorizations. Prime factorizations help in finding the GCF and LCM of integers. Finding the GCF helps in reducing fractions. Finding the LCM helps in adding and subtracting unlike fractions. Carpenters do this. Chefs do this. It's entirely possible you will have no need of this, but it's better to know something and not need to use it then not know something you need to use. If you have children of your own, you can help them with their math homework.
Only composite numbershave prime factorizations. Prime factorizations must consist of only prime numbers.
(a) what is the prime factorization of 5184 using exponents? (b)Use the answer (a) to find the square root of 5184
Prime numbers help you to find the LCM and the GCF.
Example: 30 and 42 2 x 3 x 5 = 30 2 x 3 x 7 = 42 2 x 3 x 5 x 7 = 210, the LCM
2 x 3 x 3 = 18 3 x 7 = 21 2 x 3 x 3 x 7 = 126, the LCM
Example: 30 and 42 2 x 3 x 5 = 30 2 x 3 x 7 = 42 Combine the factors, eliminating duplicates. 2 x 3 x 5 x 7 = 210, the LCM
To find the GCF and the LCM you have to first at least try to use prime factorization. So use factor trees. Or for the LCM find th least common multiples of the number.
speed you can just use your brain to find the LCM faster, sometimes.
You need at least two numbers to find an LCM no matter what you use.