Предмет: Математика, автор: lucenkooksana

1). Если каждая девочка принесет по 5 грн., а каждый мальчик по 7 грн., то все 25 учеников принесут 147 гривен в общую кассу класса.Кого и на сколько в классе больше?
А) девочек на 3
Б)мальчиков на 3
В) девочек на 4
Г) мальчиков на 4
2). Сколько существует натуральных чисел, в результате умножения которых на 19 произведение будет большим от 320,но меньшим от 360?
А) один
Б) два
В) три
Г) четыре
3) На соривнованиях спотсмены одной команды выиграли 26 медалей, из них 15 золотых и бронзовых, 18 золотых и серебряных.Сколько серебряных медалей они выиграли?
А) 7
Б) 8
В) 9
Г)11

Ответы

Автор ответа: evo4ka77
1

Ответ:

1.А)

2.Б)

3.все кажется правильным


elinasam55: неправильно решено
Автор ответа: rjyatnrf67
1

Ответ:

1-а

2-2

3-г

Пошаговое объяснение:

1- пусть к-во дев-х, а у- к-во мальчиков, тогда  5х+7у=147 и х+у=25 отсюда х=14, у=11

2. два числа -17 и 18

3. х - золотые, у - бронз, е- серебр.

х+у=15 и х+е-18 , у=15-х, е=18-х  тогда  (15-х)+х+(18-х) = 26

х-7    А  серебр е=18-7=11 шт

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9 Read the text. Choose the correct answers.
In January 2015, Kevin Jorgeson and Tommy Caldwell climbed to the top of the Dawn Wall of

El Capitan – a famous mountain in Yosemite National Park, USA. This is often described as

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used ropes to protect themselves from falling, but not to help them climb.

Kevin Jorgeson nearly didn't finish the climb. He found one part of the Dawn Wall extremely

difficult. It took him seven days to do this part, and he fell eleven times. His fingers were

damaged too, so he had to wait for them to get better before he could continue. But in the

end, both men finished the climb together. It was an amazing achievement.

Only two weeks later, an ice climber called Will Gadd became the first person to climb a

frozen part of the Niagara Falls. These falls, on the Niagara River between America and

Canada, are the biggest waterfalls in North America. They are made of three separate

waterfalls, and Gadd climbed the Horseshoe Falls, on the Canadian side. In winter, a part of

these 50.9 metre falls freezes, and Gadd wanted to climb up the ice. But it was an extremely

difficult climb. The ice was very thick in some places, but not in other places. And because

only a part of the waterfall was frozen, a lot of water fell past Gadd as he climbed. Gadd knew

that if he fell, he would probably die − but he got to the top.

But why do people want to do dangerous climbs like these? 'Dangerous situations are very

exciting,' says climber Terrence Jones. 'They make you feel alive.' Humans have always

looked for challenges, but many of the old challenges – like climbing Mount Everest – aren’t

exciting enough for some climbers because so many people have already done them.

‘Climbers like Caldwell and Gadd want to achieve more than anyone else,’ says Jones, ‘so

that the world will read about them in the papers and see them on TV.’

One day people will complete all of the difficult climbs on Earth, so what will climbers do then?

‘I don’t know,’ says Jones. ‘But perhaps one day far in the future people won’t climb on Earth.

There are still mountains to climb on Mars!’ This may never happen, of course, but one thing

is certain: the search for adventure will not stop.

1 Why was the Dawn Wall difficult to climb?

a It was higher than the climbers thought.

b The climbers couldn’t sleep.

c The rocks were difficult for climbers to hold.

d It took a very long time to finish.

49 Jorgeson had to stop climbing for a while because

a he was really tired.

b he was anxious.

c he often slipped.

d he had an injury.

50 What does the text say about Will Gadd's climb?

a Nobody had climbed that section of the falls before him.

b He climbed the highest part of the Niagara Falls.

c It was the most dangerous climb in the world.

d Nobody had climbed on ice in Canada before.

51 Terence suggests that Gadd and Caldwell climb

a to become famous.

b to write about their experiences.

c to make TV programmes.

d to show people how difficult climbing is.

52 In this article, the writer

a encourages people to go on adventures.

b discusses people who do difficult things.

c describes why he likes doing dangerous climbs.

d predicts the future of climbing.