Предмет: Математика, автор: Tokiarunino

Туристы за три дня проехали 460 км. Путь их в первый день относится к пути во второй день как 7:5. Отношение пути туристов во второй день к пути в третий день равно 3:2. Сколько километров они проехали в первый, во второй, в третий день ?

Ответы

Автор ответа: zews1065
0
предположим что в первый день путь составил - х1 км, во второй - х2, в третий - х3. Теперь запишем данные из задачи:
х1+х2+х3=460 км,
х1/х2=7/5, отсюда находим х1=7/5 х2
х2/х3=3/2, отсюда находим х3=2/3 х2
подставляем в первое условия х1 и х2, получаем:
7/5 х2+х2+2/3 х2=460, для простоты умножим обе части на 15 (наименьший знаменатель): 21х2+15х2+10х2=460х15
46х2=460х15, х2=150 км,
теперь находим х1=7/5 150=210 км,
и х3=2/3 150=100 км.
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