A car runs $16km$ using $1$ $\text{litre}$ of petrol. How much distance will it cover using $2\frac{3}{4}$ $\text{litre}$ of petrol?

A mixed fraction can be converted into improper fraction by multiplying the denominator by the whole number and adding the result to the remainder while keeping the denominator unchanged.

$2\frac{3}{4}=\frac{2\times 4+3}{4}=\frac{11}{4}$

Multiply $\frac{11}{4}$ by $16$ to obtain the distance the car wll cover using $2\frac{3}{4}\text{litre}$ of petrol.

$\frac{11}{4}\times \frac{16}{1}=\frac{176}{4}$

$=\frac{44}{1}$

$=44$

Hence, the car will cover $44km$ using $2\frac{3}{4}\text{litres}$ of petrol.