# Qual è la scomposizione in fattori primi di 180?

#### Risposta:

180=2^2xx3^2xx5

#### Spiegazione:

We have to obtain the factors of 180 which are color(blue)"prime numbers"

Acolor(blue)" prime number" being a number with only 2 factors.That is 1 and the number itself.

For example "5 only has 2 factors 1 and 5"rArr5=1xx5

Here are the first few color(blue)"prime numbers"

2,3,5,7,11,13,.....

A number which is not prime is a color(red)"composite number". Composite numbers have more than 2 factors. All composite numbers can be expressed as a product of prime factors.

For example 10 has factors 1 ,2 ,5 and 10 but can be expressed as a product of prime factors.

rArr10=2xx5

Esistono diversi modi per trovare i fattori primi di un numero. Eccone uno.

Starting with 180, divide it by the lowest prime number 2 , repeat until it cannot be divided by 2 and move on to next prime number 3 and so on. When the remainder is 1 stop-we have obtained our prime factors.

•180÷color(red)(2)=90

•90÷color(red)(2)=45 " which cannot be divided by" 2to3

•45÷color(red)(3)=15

•15÷color(red)(3)=5" which cannot be divided by" 3to5

•5÷color(red)(5)=1" having reached 1, we are there"

rArr180=color(red)(2xx2xx3xx3xx5)=2^2xx3^2xx5