If we have a decimal number and we want to convert it to a fraction, we can start by multiplying (and also dividing) by 10^n, being n the number of decimals of the number.
In this case, 2.16 has 2 decimal places, so we have to multiply and divide it by 10^2=100.
Then, we get:
![2.16\cdot(100)/(100)=(2.16\cdot100)/(100)=(216)/(100)](https://img.qammunity.org/2023/formulas/mathematics/college/37sljz7depqj28j6c1i7kqzrgcbm745o3g.png)
We already have a fraction: 216/100, but we can try to simplify if looking for common factors:
![\begin{gathered} 216=2\cdot108=2\cdot2\cdot54=2\cdot2\cdot2\cdot27=2^3\cdot3\cdot9=2^3\cdot3\cdot3\cdot3=2^3\cdot3^3 \\ 100=2^2\cdot25=2^2\cdot5^2 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/bqmkpvbp7qr0abmpe3autl7hl5vtxf1hc5.png)
We have 2^2=4 as common factor between numerator and denominator, so we can simplify the fraction as:
![((216)/(4))/((100)/(4))=(54)/(25)](https://img.qammunity.org/2023/formulas/mathematics/college/cbzb8py3ki60gq0q0j2m39sqf5ev2x5myh.png)
Answer: 2.16 as a fraction is 54/25.