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Помогите пожалуйста. На математической викторине ученикам предложили 20вопросов.За каждый правельный ответ ученику ставили 15 баллов, а за неправильный снимали 8баллов.Сколько правельных ответов дал ученик ,если он ответил на все вопросы и набрал 116 баллов?
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Предмет:
Математика -
Автор:
ariel1 - 5 лет назад
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Ответы 1
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Скажем ученик ответил на x вопросов правильно, относительно он ответил неправильно на 20-x вопросов. Вес ОДНОГО правильного ответа составляет 15 баллов, и неправильного 8 баллов:15x - ( 20-x)8=11615x + 8x-160= 11623x= 276x=12ОТВЕТ: Он дал 12 правильных и 8 неправильных ответов
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Автор:
zackfqm6 - 5 лет назад
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0
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Сделайте пожалуйста пересказ текста на английском
Since ancient times Nature has served Man, being the source of his life. For thousands of years people lived in harmony with environment and it seemed to them that natural riches were unlimited. But with the development of civilization man's interference in nature began to increase.
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