Question

What are the factors of $ 18,19 $ and $ 200 $

Answer 1

Hint: First, we will need to know about the prime numbers and composite numbers concepts.
Prime numbers are the numbers that are divisible by themselves and $ 1 $ only or also known as the numbers whose factors are the given number itself.
Composite numbers defined as the numbers having more than two factors ( $ 1 $ , itself and any other numbers)
Hence in the number system, there is only a possibility that the number is either prime or composite.

Complete step by step answer:
Since from the given question, they asked to find the factors of the three numbers which are $ 18,19 $ and $ 200 $
Every number has two factors which are $ 1 $ and itself.
 $ A)18 $
Starting with the number $ 18 $ and the factors will not exceed this number $ 18 $ and remainder needs to $ 0 $
Now simply divide the number by every other number which is less than $ 18 $
Which are $ \dfrac{{18}}{1} = 18 $ (as we said $ 1 $ is the factor of any numbers)
 $ \dfrac{{18}}{2} = 9,\dfrac{{18}}{3} = 6 $ are the factors too as they get the remainder zero.
 $ \dfrac{{18}}{4},\dfrac{{18}}{5} $ are not completely divisible and proceeding the same way up to the number $ 18 $
Thus, we get the factors as $ 1,2,3,6,9,18 $ which are the number when divisible to $ 18 $ and get the remainder as $ 0 $
 $ B)19 $
Now proceed the same way with the number $ 19 $
But the number $ 19 $ is the prime number as it has the only factors which are $ 1 $ and itself.
Hence, we get the factors of $ 19 $ are $ 1,19 $
 $ C)200 $
Now we proceed with the number $ 200 $ in the same way.
The number $ 200 $ has the factors with the remainder zero as
 $ \dfrac{{200}}{1},\dfrac{{200}}{2},\dfrac{{200}}{4},\dfrac{{200}}{5},\dfrac{{200}}{8},\dfrac{{200}}{{10}},\dfrac{{200}}{{20}},\dfrac{{200}}{{25}},\dfrac{{200}}{{40}},\dfrac{{200}}{{50}},\dfrac{{200}}{{100}},\dfrac{{200}}{{200}} $ (Will not exceed $ 200 $ )
Since only if we divide the number $ 200 $ with these numbers above, then we get the remainder zero.
Therefore, the factors of a number $ 200 $ are $ 1,2,4,5,8,10,20,25,40,50,100,200 $
Hence the factors $ 18 $ are $ 1,2,3,6,9,18 $
Factors of $ 19 $ are $ 1,19 $
Factors of $ 200 $ are $ 1,2,4,5,8,10,20,25,40,50,100,200 $

Note: Since from the given numbers $ 18,19,200 $ the composite numbers are $ 18,200 $ (which have more than two factors other than one and itself) and the prime number is $ 19 $ (only factors are one and itself)
Every number greater than $ 1 $ can be divided by at least one prime number.
 $ 2 $ is the only even prime number.
If the number is not a prime number, then it is known as the composite number.