Предмет: Математика, автор: fidchenko92

реши задачу После уроков ребята устроили уборку 5 мальчиков и 7 девочек вымыли все столы в классе Каждый из детей вымыл одинаковое количество столов , но девочки на 4 стола больше сколько всего столов ?

Ответы

Автор ответа: MAMAN9

Каждый ученик вымыл х парт.

Всего девочки вымыли 7*х, а мальчики 5*х.

При этом разность всех парт, вымытых девочками и мальчиками, равна 4.

Составляем уравнение:

7х-5х=4;

2х=4;

х=2.

Всего мальчики вымыли 5*2=10 парт,

а девочки 7*2= 14 парт;

Всего: 14+10=24 - столько всего столов.

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