Предмет: Математика, автор: Наськаа1

Поезд идет со скоростью 40 кмч По наблюдению машиниста встречный поезд, длина которого 75 м, проходит мимо за 3 сек. Какова скорость движения встречного поезда?

Ответы

Автор ответа: levzaharov
0

Общая скорость = 75/3 = 25 м/с = 90 км/ч.

Значит скорость поезда равна = 90 - 40 = 50 км/ч

Автор ответа: marinka31
0

v1+v2=S/t  -движение навстречу    40+v2=0,075/1:1200(75м=0,075 км,3сек.=1:1200)       40+v2=90    v2=90-40  v2=50 км/ч  ответ:50км/ч

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