Question:  $\dfrac{2}{7}$~of the audience at a play were adults.~$\dfrac{4}{5}$~of the remaining audience were boys and the rest were girls. Given that there were $$80$$ more adults than girls, how many people were there at the play?     Adriana\textquotesingle s workings:  Girls $=1-\frac{4}{5}=\frac{1}{5}$ of the remainder  $=\frac{1}{5}\times\frac{2}{7}$  $=\frac{2}{35}$  Adults $=\frac{2}{7}$  Difference $=\frac{2}{7}-\frac{2}{35}=\frac{8}{35}$ $\to$ $80$ people  Total people $=\frac{80}{8}\times35=350$ people.     Now, let\textquotesingle s look at Adriana\textquotesingle s workings for the question. Is there any mistake? Solve the problem and show all workings. There were~\uline{~~~~~~~~~~}~people at the play. 
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