How to write 251100 as a decimal number?

${\displaystyle \frac{251}{100}}$ is a mixed fraction.
the fraction ${\displaystyle \frac{51}{100}}$ is not a decimal,
Divide the numerator by the denominator in order to convert fractions to decimals.
numerator = 51
denominator = 100
${\displaystyle \frac{51}{100}=0.51}$
${\displaystyle 0.51+2=2.51}$
That means ${\displaystyle \frac{251}{100}}$ = ${\displaystyle 2.51}$
When converting fractions into decimal, the equation is ${\displaystyle \frac{n}{d}}$
n = numerator = 51
d = denominator = 100
${\displaystyle \frac{51}{100}=0.51}$
Converting a mixed fraction into a decimal number is done by using the equation
${\displaystyle w+\frac{n}{d}}$
w = whole number = 2
n = numerator = 51
d = denominator = 100
${\displaystyle 2+\frac{51}{100}=2.51}$