How to calculate a whole amount with fractions?

Question

A contractor first completes $7/16$ of a building. Then he completes $1/4$ of it. And finally completes $2/5$th of the remainder of the building. If there is $36$ days left to finish the construction of the building, how many days in total would it take to finish it completely? (The answer is supposed to be $192$ days)

Answer 1

HINT Find the amount of work remaining

$\frac{7}{16}+\frac{4}{16}+(1-\frac{11}{16})*\frac{2}{5}$