Предмет: Математика, автор: Макс558

Расстояние между Москвой и Рязанью составляет 200 км. Настя и Лена договорились встретиться в городе Коломна, который расположен между Москвой и Рязанью на расстоянии 80 км от Рязани. Настя выехала на автомобиле из Москвы в 08:15 и едет со скоростью 80 км/ч. Во сколько должна выехать из Рязани Лена, чтобы прибыть в Коломну одновременно с Настей, если Лена передвигается на мопеде со скоростью 50 км/ч?

Ответы

Автор ответа: ndusha

200-80=120км проедет Настя
120/80=12/8=3/2=1,5ч=1ч 30м будет ехать Настя
8ч15м+1ч30м=9ч45м-во столько Настя приедет в Коломну
80/50=8/5=1 3/5ч=1ч36м будет ехать Лена
9ч45м-1ч36м=8ч9мин-во столько надо выехать Лене

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