Предмет: Математика, автор: Аноним

В цистерне было 480ведер воды. один насос может выкачать всю воду за 24 мин ,а другой-за40мин . за сколько минут можно выкачать всю воду если сразу включить сразу два насоса ?

Ответы

Автор ответа: Peremena7777
0
скорость первого
480/24=20 в/мин
скорость второго
480/40= 12 в/мин
значит работая вместе они выкачают за
480/(20+12)=480/32=15 минут
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