Question

Срочно надо,пожалуйста

Answer 1

$\frac{3m}{15sm} = \frac{300}{15} = 20 \\ \frac{3h}{45min} = \frac{180min}{45min} = 4 \\ \frac{7.5kg}{250g} = \frac{7500g}{250g} = 30 \\ \frac{31}{31} = 1 \\ \frac{999}{10} = 99.9$

там h - это час.