Вопрос школьника по предмету Математика
Решите пожалуйста задачу, даю
30 баллов)
Сплав меди и олова содержит 45% меди. Чего больше в сплаве: меди или олова, и на сколько, если масса сплава равна 84 кг?
Ответ учителя по предмету Математика
Весь сплав=84кг=100%
||
/
1) 84:100%=0,84(кг) — масса одного процената
2) 45%*0,84=37,8(кг) — масса меди в сплаве
3) 84-37,8=46,2(кг) — масса олова в растворе
4) 46,2-37,8=8,4(кг)
Ответ: в растворе олова на 8,4 кг больше, чем меди.
Похожие вопросы от пользователей
When we want to buy something, we must go to the shop where it is sold. In the shop window we see what is sold in the shop. Sugar, tea, coffee, salt, pepper, ham, bacon, and so on are sold at the grocer’s. Bread is sold at the baker’s, meat at the butcher’s. We go to the greengrocer’s for vegetables and fruit. We buy boots and shoes at the shoe-shop. We buy books at the bookseller’s and jewellery and watches at the jeweller’s. The salesman or salesgirl stands behind the counter. We ask the salesman: “How much is this?” or “What is the price of that?” He tells us the price. He gives us the bill. At the cashdesk we give the money and the bill to the cashier, who gives us a check and our change. The salesman wraps up the goods and gives them to us. We put them in our bag. Some shops have many departments. We can buy nearly everything we need there. These are called department stores. In some shops there are no salesmen, but only cashiers. The customers choose the goods they want and pay at the cashdesk. These are called self-service shops. If someone tries to take things from a shop without paying they are almost certain to be caught. Most shops have store detectives who have the job catching shoplifters. Shoplifting is considered a serious crime by the pol
На олимпиаде по химии участников рассаживают по трём аудиториям. В первых двух по 180 человек, оставшихся проводят в запасную аудиторию в другом корпусе. При подсчёте выяснилось, что всего было 450 участников. Найдите вероятность того, что случайно выбранный участник писал олимпиаду в запасной аудитории.
33m-1024=m