Вопрос школьника по предмету Математика
Пассажир поезда, идущего со скоростью 79,2 км ч , заметил , что встречный поезд шёл мимо него в течении 12 секунд . Определите скорость встречного поезда , если его длина 480 метров
Ответ учителя по предмету Математика
480_12=40 м/ сек скорость прохождения поездов
переведем 40 м / с в км / ч
40 м/ сек* 3600 сек: 1000=144 км/ ч
144-79,2=64,8 км/ ч скорость встречного поезда
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