Предмет: Математика, автор: vuser

1 Арман рисовал радугу. У него в наборе 7 цветов красок. Сначала он решил выбрать два цвета. Сколькими спосо бами можно выбрать два цвета красок из набора? 90 Смог ли ты решить такую задачу? В жизни часто приходится решать и другие задачи на комбинации. Например, сколько имеется вариантов школьного расписания.​

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Ответы

Автор ответа: AngelinaKretsul
2

Ответ: 21 способ

Пошаговое объяснение:Первый цвет 7-ю способами, второй 6-ю. Всего 7·6 = 42 способа. Но среди них есть пары одинаковых наборов цветов. Например, первый жёлтый, второй синий и первый синий, второй жёлтый. Если считать такие наборы одинаковыми, то всего 42:2 = 21 способ.

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NAME: .......................................................................................................................
CLASS: ...........................................................................................

1.Use some, much, many, no, a lot of, any, a little, few.
I don’t have _____ bread, so I have to buy ________.
I can’t talk to you now, I have got ________ time.
Sarah drinks ___________ cola. It’s not good.
I can cook an apple pie. There’s _________ milk.
I can’t cook an apple pie. There’re ________ eggs.
I am not very busy today. I haven’t got _________ to do.
I haven’t got ________ friends. But I can rely on them.

2. Make a list of things you would like to buy in the following shops (imagine that you’ve won a big sum of money):
Pet shop
Clothes shop
Toy shop
Sport's shop
Stationery shop
Optician’s
Chemist’s
Jeweller’s
Electronics shop



























































































3. Translate the sentences into English. Use the present perfect simple or continuous.
Я хожу по магазинам уже 3 часа и очень устал.
______________________________________________________
Я только что купил фотоаппарат.
______________________________________________________
Я уже читал эту книгу, она очень интересная.
______________________________________________________
Я читаю эту книгу с 3 часов.
______________________________________________________

4. Read the e-mail from Angela at p. 90 SB and mark the sentences T (True) or F (False).
Angela is in York, UK. _____
She bought a silver frame for Wendy. _____
It’s very difficult to buy a present for her dad. _____
She will come back in a few days. _____
Her brother Tim will love the silver robot. _____
Her grandma will get a striped bag as a gift from New York. _____

5. Change the sentences into the past continuous. You may need
to add adverbs of time.
• Bill and Louise walked home from school together yesterday.
• ____________________ _____________________________________________________
• Laura went upstairs and opened the window.
• _______________ __________________________________________________________
• Tom listened to his new CD before going to sleep.
• _______________________ __________________________________________________
• Sarah worked at her art project last month.
• _________________________ ________________________________________________
• We travelled around Russia last summer.
• _________________________________________________________________________


6. Choose the correct variant:
1. There isn’t a cloud in the sky, but it (be) cloudy yesterday.
• is
• was
• were
2. Mr. Wilson usually finishes his work at half past three, but he (finish) it later
yesterday afternoon.
• finish
• finishes
• finished
3. We usually have lunch at 12.30, but yesterday we (have lunch) later.
• had lunch
• have lunched
• had had lunch
4. The Browns live in a five-room apartment, but last year they (live) in a small
house in the country.
• were living
• did live
• lived
5. How you (cut) your finger?
• How have you cut
• How you cutted
• How did you cut
6. When you (write) to your parents last time?
• When do you writed
• When did you write
• When did you wrote
7. We (not/have) a holiday last year.
• didn’t have
• haven’t had
• haven’t had

Помогите пожалуйста❤️​