Предмет: Математика, автор: lili5007

туристы проплыли на лодке 2,4 ч по течению реки и 1,8 часа против течения,при этом по течению их путь был на 14,1км больше,чем против течения.Найдите скорость лодки в стоячей воде,если скорость течения реки равна 2,5км/ч.
решите с уравнением!!!

Ответы

Автор ответа: anmih
0
Пусть х км/ч собственная скорость лодки, составляем таблицу:
                              скорость    время     расстояние
течение реки        2,5 км/ч         ---             ---
собств лодка         х км/ч           ---             ---
по течению           х+2,5 км/ч     2,4 ч      на 14,1 км >
против течения    х-2,5 км/ч      1,8 ч                        

по условию задачи составляем уравнение:
2,4(х+2,5)-1,8(х-2,5) = 14,1
2.4x + 6 - 1.8 x +4.5 = 14.1
0.6x = 14.1 -4.5-6
0.6 x = 3.6
x= 3.6 : 0.6
x= 6 км/ч - собственная скорость лодки



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