Question

What percent of $10{\text{kg}}$ is $250{\text{g}}$?
A) $25\% $
B) $5\% $
C) $10\% $
D) $2.5\% $

Answer 1

Hint:
Here, we will assume the percentage as a variable. Then, we will form a mathematical expression using the given information. Solving the expression further will give us the required percentage.

Formula Used:
$1{\text{kg}} = 1000{\text{g}}$

Complete step by step solution:
Now, in this question, it is asked to find what percentage of $10{\text{kg}}$ is $250{\text{g}}$
We know that ‘Percentage’ means ‘per 100’ or we can say that percentage is that number which can be expressed as a fraction of 100 or by just using the $\% $ sign.
First, we will use the conversion formula and convert $10{\text{kg}}$ into grams to make the units the same.
Now, as we know, $1{\text{kg}} = 1000{\text{g}}$
Therefore, $10{\text{kg}} = 10,000{\text{g}}$
Let $x\% $ of $10,000{\text{g}}$be $250{\text{g}}$.
Therefore, writing mathematically we can write,
$ \Rightarrow x\% \times 10000 = 250$
Now converting the percentage into fraction, we get
$ \Rightarrow \dfrac{x}{{100}} \times 10000 = 250$
Dividing 10000 by 100, we get
$ \Rightarrow x \times 100 = 250$
Dividing both sides by 100, we get
$ \Rightarrow x = \dfrac{{250}}{{100}} = 2.5$
Therefore, $2.5\% $ of $10{\text{kg}}$ is $250{\text{g}}$.

Hence, option D is the correct answer.

Note:
In this question it is asked that what percentage of $10{\text{kg}}$ is $250{\text{g}}$, this could be misinterpreted and misread and hence, we could make the equation as:
$250 \times x\% = 10$
Here, it is also important to convert the kilogram into grams because we can only mathematically operate two terms if they have the same units. If we try to find the percentage without converting the units, we will get the wrong answer.