If a box of sweets is divided among $24$ children, they will get$5$ sweets each. How many would each get, if the number of the children is reduced by $4$?

A contractor estimates that $3$ persons could rewire Javaid's house in $4$ days, If, he uses $4$ persons instead of three, then they take $k$ days to complete the job. Find the value of $k$.

A batch of bottles is packed in $25$ boxes with $12$ bottles in each box. If the same batch is packed using $20$ bottles in each box, how many boxes would be filled? (Write the numeral part as the final answer).

A factory requires $42$ machines to produce a given number of articles in $63$ days. How many machines would be required to produce the same number of articles in $54$ days?

Two persons could fit new windows in a house in $3$ days. One of the persons fell ill before the work started. If the job will take now $k$ days, then the value of $k$ is

Two persons could fit new windows in a house in $3$ days. If the number of persons needed to fit the windows in one day is $k$, then find the value of $k.$