• question_answer 11)                 In a stack there are 5 books each of thickness 20 mm and 5 paper sheets each of thickness 0.016 mm. What is the total thickness of the stack?

Total thickness of books         $=5\times 20\,mm\,=\,100\,mm$ Total thickness of paper sheets        $=5\times 0.016\text{ }mm=0.080\text{ }mm$ $\therefore$ Total thickness of the stack = Total thickness of books + Total thickness of paper sheets $=100\,\,mm\,+0.080\,\,mm$ $=(100=0.080)\,mm$ $=100.080\,\,mm$ $=1.0008\times {{10}^{2}}mm.$