Предмет: Математика, автор: tvangel475

За 5 кг винограду і 2 кг груш заплатили 780 грн. За 1 кг винограду і 3 кг груш заплатили 390 грн. Знайдіть вартість 1 кг винограду.​

Ответы

Автор ответа: Gorobets23
1

Пусть х грн-стоит 1кг винограда

у грн-стоит 1кг груш

Получаем ситему ур-ний

5х+2у=780

х+3у=390 - умножим на 5 и вычтем первое ур-ние

5х+2у=780

5х+15у=1950

13у=1170

у=1170/13

у=90

х+3*90=390

х+270=390

х=390-270

х=120

ответ: 120 грн-стоит 1кг винограда и 90 грн-стоит 1кг груш.

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