Предмет: Математика, автор: Каринa2006

написать краткую запись к этой задаче:
Туристы отправились на прогулку на катере. Они проплыли 36 км по течению реки, сделали привал на 3 часа и затем вернулись обратно. Сколько времени заняла вся прогулка, если собственная скорость катера 15 км/ч, а скорость течения реки 3 км/ч?

Ответы

Автор ответа: vmaluga2011
0
Sпо теч - 36 км
Sпротив - 36 км
Vсобств - 15 км/ч
Vтеч - 3 км/ч
tпривала - 3 ч
tобщ - ?

15 км/ч+3 км/ч=18 км/ч скорость по течению
36 км:18 км/ч=2 ч  плыли по течению
15 км/ч-3 км/ч=12 км/ч  скорость против течения
36 км:12 км/ч=3 ч  плыли против течения
2 ч+3 ч+3 ч=8 ч
Ответ: прогулка заняла 8 часов
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