Вопрос школьника по предмету Математика
Помогите пожалуйста решить уровнение пользуясь основным свойством пропорции (0,1у+5):2=(0,6у-4):5
Ответ учителя по предмету Математика
(0,1у+5):2=(0,6у-4):5
Основное свойство пропорции:
Произведение крайних членов равно произведению средних.
2(0.6у-4)=5(0.1у+5)
1.2у-8=0.5у+25
0.7у=33
х=330/7
х=47 1/7
Ответ: 47 1/7
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