Answer:
I suppose that we want to know if:
1.567 is a rational number.
Ok, we know that a rational number is a number that can be written as the quotient between two integer numbers, such as:
a/b
where a and b are integer numbers.
So let's try to write 1.567 in that form.
One thing that we can do, is to multiply it and divide it by the same number (this does not change the number, is equivalent to multiply by 1).
First, let's count the number of decimals after the decimal point, if we have N decimals, we need to multiply and divide by 10^N
in this case, we have N = 3.
Then we need to multiply and divide by 10^3.
10^3 = 10*10*10 = 1000
We need to multiply and divide by 1000.
We will get:
1.567 = 1.567*(1000/1000) = (1.567*1000)/(1000) = 1567/1000
That is the quotient between two integer numbers, then we can conclude that 1.567 is an integer number.