Question

$25$ mm is equal to how many cm?

Answer 1

Hint:
In the given question, the mm(millimeter) is equal to how much cm(centimeter). The given question is the relationship between centimeter and millimeter. As we know $1$ meter is equal to $100$ cm that is $1{\text{ m}} = 100{\text{ cm}}$. And mm is the smallest unit of cm. Which is $1{\text{cm}} = 10{\text{ mm}}$. Therefore the relation between meter and millimeter becomes $1{\text{ m}} = 1000{\text{ mm}}$

Complete step by step solution:
The given question is to convert the given millimeters in centimeters.
Before doing this we should be very clear about these metric terms.
We have meter and $1{\text{ metre}} = 100{\text{ cm}}$
and $1{\text{cm}} = 10{\text{mm}}$
Therefore $1{\text{m}} = 100{\text{cm }} = 100 \times 10{\text{mm}}$
Therefore $1{\text{m}} = 1000{\text{mm}}$
Now the given question is about millimeters and centimeters
$1{\text{m}} = 100{\text{mm}}$
But in the question, we have to convert \[{\text{25mm}}\]
into can because it is asked that \[{\text{25mm}}\] is equal to how much cm
Therefore \[{\text{1cm = 10mm}}\]
means \[\dfrac{1}{{10}}{\text{cm = 1m}}\]
which means \[{\text{1m}}\dfrac{1}{{10}}{\text{cm}}\]
But we want to convert \[{\text{25mm}}\] into \[{\text{cm}}\]
Therefore on multiplying both side by \[{\text{25}}\]
We get
\[{\text{1mm}} \times {\text{25 = }}\dfrac{1}{{10}} \times {\text{25cm}}\]
\[ \Rightarrow {\text{25mm = }}\dfrac{{25}}{{10}}{\text{cm}}\]
Now making the factors of \[25{\text{ \& }}10\] up get
\[25 = 5 \times 5{\text{ and }}10 = 2 \times 5\]
we get \[{\text{25mm = }}\dfrac{{5 \times 5}}{{2 \times 5}}{\text{cm}}\]
Where $5$ in numerator and denominator gets cancel
\[{\text{25mm = }}\dfrac{5}{2}{\text{cm}}\]
When we divide $5$ by $2$, we get $2.5$

Therefore \[{\text{25mm = }}2.5{\text{cm}}\]

Note:
The given question was to convert ${\text{mm}}$ to ${\text{cm}}$ Since \[{\text{1mm = }}10{\text{mm}}\] but we want to convert
${\text{mm}}$ to ${\text{cm}}$, therefore \[{\text{1mm = }}\dfrac{1}{{10}}{\text{cm}}\]
Also ${\text{1}}$ meter is equal to ${\text{100cm}}$ Therefore \[{\text{1cm = }}\dfrac{1}{{10}}{\text{metres}}{\text{. Also }}1{\text{m}} = 1000{\text{mm}}\]
Therefore \[{\text{1mm = }}\dfrac{1}{{1000}}{\text{m}}\] There are the relations to convert $m{\text{, }}cm{\text{ and }}mm$ into each other.