Fill in the blank box in each of the following:

$\frac{1}{3}=\frac{\left[\right]}{18}$

Q. Fill in the blank box in each of the following:

(iv)$\frac{7}{\left[\right]}=\frac{21}{18}$numerator

Fill in the blank box in each of the following:

$\frac{5}{9}=\frac{[]}{81}$

Fill in the blanks:

$-18+\left(-28\right)=\_\_\_\_\_\_$

Fill in the blanks:

$\_\_\_\_\_+\left(-18\right)=4$

In the following the box is to be filled by the same integer. Find the value of the integer in each case.

$(-3)\times \left[\_\right]=\left[\_\right]=\left[\_\right]÷(-3)$