1.
[tex]0.7 = 70\%[/tex]
[tex]72 - 100\% \\ x - 70\% \\ \\ x = \frac{72 \times 70}{100} = \frac{72 \times 7}{10} = \frac{36 \times 7}{5} = \frac{252}{5} 50 \frac{2}{5} = 252.4[/tex]
[tex]0.27 = 27\%[/tex]
[tex]90 - 100\% \\ x - 27\% \\ \\ x = \frac{90 \times 27}{100} = \frac{9 \times 27}{10} = \frac{243}{10} = 24.3[/tex]
2.
[tex]0.6 = 60\%[/tex]
[tex]60\% - 84 \\100\% - x \\ \\ x = \frac{100 \times 84}{60} = \frac{5 \times 84}{3} = \frac{420}{3} = 140[/tex]
[tex]0.26 = 26\% [/tex]
[tex]26\% - 46.8 \\ 100\% - x \\ \\ x = \frac{100 \times 46.8}{26} = \frac{50 \times 46.8}{13} = \frac{2340}{13} = 180[/tex]
3.
[tex]0.4 = 40\%[/tex]
[tex]100\% - 280 \\ 40\% - x \\ \\ x = \frac{40 \times 280}{100} = \frac{2 \times 280}{5} = 2 \times 56 = 112[/tex]
[tex]280 - 112 = 168[/tex]
Odpowiedź: Musi jeszcze przeczytać 168 stron
4.
[tex]0.7 = 70\%[/tex]
[tex]147 - 70\% \\ x - 100\% \\ \\ x = \frac{147 \times 100}{70} = \frac{147 \times 10}{7} = \frac{1470}{7} = 210[/tex]
Odpowiedź: Książka ma 210 stron
Myślę że pomogłem ;)
