Предмет: Математика, автор: lorennna

Всем здравствуйте! Помогите решить! Не могу :(

Велосипедист и пешеход, двигающиеся навстречу друг другу одновременно из пунктов А и В, встретились через 2 часа. Расстояние между пунктами 30 км.

С какой скоростью двигался пешеход, если велосипедист проезжал в час на 3 км больше, чем пешеход?
Изменится ли решение задачи, если велосипедист будет двигаться в два раза быстрее, чем пешеход?

Ответы

Автор ответа: vmaluga2011
0
30:2=15 (км/ч) скорость сближения или сумма скоростей
(15-3):2=12:2=6 (км/ч) скорость пешехода
Ответ: скорость пешехода 6 км/ч

Да решение немного изменится:
30:2=15 (км/ч) сумма скоростей
1 часть - пешеход
2 части - велосипедист
1+2=3 части всего
15:3=5 (км/ч) скорость пешехода
Ответ: скорость пешехода 5 км/ч

Можно эту часть задачи решить и уравнением
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