Question

Decimal form of $\dfrac{{3888}}{{1000}}$ is
A. $38.88$
B. $3.888$
C. $388.8$
D. $0.3888$

Answer 1

Hint:We usually place the decimal before the number of digits that is equal to the number of zeroes in the denominator. Suppose here in $1000$, we have three zeroes so we place the decimal after the three digits in the numerator from the right side but first of all check whether it is terminating or non-terminating.

Complete step-by-step answer:
Here in this question, we are given to write the decimal form of $\dfrac{{3888}}{{1000}}$.
So basically decimals are placed on the preceding powers of $10$ and thus when we move from left to right, the place value of the digits get divided by $10$. This means that the decimal place values determine the tenth, hundredth and the thousandth. Here I used one-tenth as $\dfrac{1}{{10}}$ and we represent it as $0.1$ in the decimal.
Similarly one-hundredth means $\dfrac{1}{{100}}$ which means $0.01$
So when we are asked to find the fraction into the decimal form, we must check whether it is a terminating or the non-terminating decimal. We know for any rational number of the form $\dfrac{p}{q}$
$q \ne 0$, if the denominator is the multiple of $2,5$ or both then it is a terminating decimal. Here we are given the term $\dfrac{{3888}}{{1000}}$
Here the denominator is $1000$
So here if we find the multiple of $1000$, we will get
$1000 = 2 \times 2 \times 2 \times 5 \times 5 \times 5$
So we can write it as
$1000 = {2^3} \times {5^3}$
Hence it is the multiple of $2,5$. So it is a terminating decimal.
 If we take $\dfrac{1}{3}$, then it will be a non-terminating decimal as in the denominator here is $3$.
So now we get to know that $\dfrac{{3888}}{{1000}}$ is a terminating decimal. So we divide it and get $3.888$

So, the correct answer is “Option B”.

Note:When the decimal does not terminate or end with the repeating sentence then they are irrational numbers where as rational numbers are terminating or repeating decimals.