Question

What percentage of $1{\text{ litre}}$ is ${\text{50 c}}{{\text{m}}^3}$?
A) $2$
B) $5$
C) $20$
D) \[50\]

Answer 1

Hint: We have given the volume in a known quantity and we just have to convert measure from one measure to another. After that we have to divide the given quantity by the known and then multiply it by hundred to calculate the percentage of the asked quantity.

Complete step-by-step answer:
The given quantity in litres is $1{\text{ litre}}$ .
We have to convert it to the unit of ${\text{c}}{{\text{m}}^3}$ .
We will have to find the conversation factor first.
We know that $1{\text{ litre = 1000 c}}{{\text{m}}^3}$ .
We have given the quantity ${\text{50 c}}{{\text{m}}^3}$ .
We need to find the percentage of it in the $1{\text{ litre}}$ .
That means we have to find the percentage of ${\text{50 c}}{{\text{m}}^3}$ in ${\text{1000 c}}{{\text{m}}^3}$ .
We will have to calculate the percentage by using the division.
Let us consider the general example.
Suppose we have to calculate the percentage of $b$ in $a$ .
We perform the following calculation in order to obtain the percentage:
$\dfrac{b}{a} \times 100$
Therefore, we will calculate the required percentage as follows:
$\Rightarrow$ $\dfrac{{50}}{{1000}} \times 100 = 5$
Therefore, the percentage of $1{\text{ litre}}$ in ${\text{50 c}}{{\text{m}}^3}$ is $5\% $ .
So, we have calculated the required percentage as shown in the process.
Hence, the correct option is B.

Note: We started by considering the given measure and we converted it to the measure that we want. The conversion factor is very much important and then we have to decide whether we have to multiply or divide the given ratio. We can make the conversions both ways so you can do it any way you want.