дано: (аn) арифмитическая прогрессия а1=12 а50=58 найти :S50 - №28065452

дано: (аn) арифмитическая прогрессия а1=12 а50=58
найти :S50
- Предмет:
  Алгебра
- Автор:
  tykehnsl
- 6 лет назад

Ответы 1

Sn=((a1+an)/2)xnS50=((12+58)/2)x50S50= (70/2)x50S50=35x50S50=1750
- Автор:
  dominic
- 6 лет назад
- 0
Добавить свой ответ

Еще вопросы

какой современный вид спорта был обязателен и популярен у средневековых рыцарей?
- Предмет:
  История
- Автор:
  jordenkn3q
- 6 лет назад
- Ответов:
  
  1
- Смотреть
дописать кубани удалось достичь в ? когда обучение в школе стало ? для всех детей. Срочноооооооооо
- Предмет:
  Окружающий мир
- Автор:
  salazar
- 6 лет назад
- Ответов:
  
  0
- Смотреть
Answer the questions on the text in written form. Письменно ответьте на вопросы по тексту (составив предложения на английском языке, без перевода).

1. Why did Harry Standish arrive at the station number 11?
2. Harry was a highly qualified customs officer, wasn’t he?
3. Where was Mrs. Harriet Mossman from?
4. What countries did she visit?
5. Why was the young officer suspicious?
6. Do officers have the right to inspect handbags and purses?
7. What did the officer find in the powder and in the tube?
At the Customs.
US Customs inspector Harry Standish arrived at Customs inspection station number eleven. Shortly before that, a red light on a wall panel near the centre the big Customs Hall indicated that an inspecting officer had a problem and needed supervisory help. Most of the passengers, who had arrived aboard Scandinavian Airlines DC-8 from Copenhagen, had cleared Customs and had left. Only this well-dressed American woman, Mrs. Harriet Mossman, who had just returned from a month trip around England, France and Denmark, insisted that all she had were shoes. The total declared value was ninety dollars – ten dollars less than she was allowed duty-free.
The young officer had been suspicious. To begin with, six dresses, all of good quality – had had their labels removed. The cut of the dresses was unmistakable French, so was the tailoring of the fur coat. The same thing was with three expensive sweaters. They also were without labels, and were unmistakable from Scotland, in typical British shades, not available in the United States. All this and much else customs officers learned as part of their training.
"Madam," Inspector Standish said, "is there anything else you wish to declare?” Mrs. Mossman answered indignantly: "There certainly isn't!”
"In that case, Madam," Inspector Standish said, "will you kindly open your handbag!” The woman protested, "But surely, purses are never inspected. I've been through Customs many times ... " "Normally, they are not. But we do have the right."
Reluctantly, Mrs. Mossman opened her purse. Harry Standish inspected a lipstick and a gold compact. When he probed the powder in the compact, he extracted a diamond and ruby ring. There was a tube of hand lotion, partially used. When he pressed the tube near the top, there was something hard inside.
He wondered when smugglers would come up with something original. Such old tricks. He had seen them all many times. He thought of the foolishness of Mrs. Mossman and the many like her. If she had been honest about the coat and dresses, and declared them the duty payable it would not have been great, especially for someone who was clearly well to do. Certainly her handbag would not have been opened and she wouldn't have been caught red-handed.
- Предмет:
  Английский язык
- Автор:
  fitzpatrick
- 6 лет назад
- Ответов:
  
  0
- Смотреть
Решите уравнение: 0,5 (5x+2) = 3,5 (x-6).
- Предмет:
  Алгебра
- Автор:
  sampson65
- 6 лет назад
- Ответов:
  
  2
- Смотреть

How much to ban the user?

1 hour 1 day 100 years