Предмет: Математика, автор: LizaVen

Решите пожалуйста задачу:
Леня заметил, что ему и старшему брату вместе 30 лет.Сколько лет Лене, если половина его лет равна трети лет брата?

Ответы

Автор ответа: ТатМих
0
х лет Лёне
у лет брату

х+у=30
frac{x}{2} = frac{y}{3} \ \ 3x=2y \ x+y=30 \ 2x+2y=60 \ \ 2x+3x=60 \ 5x=60 \ x=12 \ \ y=30-12 \ y=18

Ответ:Лёне 12 лет,брату 18 лет.
Автор ответа: красатулька2004
0
Я способ подбора.
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Предмет: Английский язык, автор: master55555mast
Профессиональный Английский Язык
2 - курс
Зачет
Тест

GRAMMAR
1 Tick (✓) A, B, or C to complete the sentences.
Example: I ________ football.
A love ✓ B loves C loving
1 Where ________?
A she is from B is she from C she from is
2 A Is Ahmet Spanish?
B No, he ________. He’s Turkish.
A is B aren’t C isn’t
3 A Who are the girls with black hair?
B ________ my sisters.
A She’s B We’re C They’re
4 A ________ your address?
B It’s 24 Green Road, London.
A Who’s B Where’s C What’s
5 A ________ your name?
B C-H-E-N-G
A How do you spell B How spell you C How you spell
6 A ________ is your sister?
B Fine. She’s in New York now.
A Who B How C Where
7 How much are ________ books?
A those B a C that
8 ________ you watch TV every day?
A Are B Is C Do
9 A Where does Jack work?
B He ________ in an office.
A works B work C does work
10 My friend ________ like meat.
A isn’t B doesn’t C aren’t
11 A Do Carlos and Maria have a car?
B ________. It’s red.
A Yes, they don’t B Yes, do they C Yes, they do
12 My sister ________ BBC and CNN.
A watchs B watches C watch
13 Anna and Jo are English, but ________ husbands are French.
A they’re B their C they are
14 My ________ house is very big.
A parents’ B parent’s C parents
15 A What’s that?
B It’s ________ umbrella.
A a B the C an
2 Put the words in the correct order to make sentences.
Example: like English I
I like English.
1 goes she by always car work to
_______________________________________.
2 housework we the usually weekend at do
_______________________________________.
3 drink I coffee 3.00 p.m. never after
_______________________________________.
4 lunch they food for eat fast sometimes
_______________________________________.
5 the husband car listens in to the usually my radio
_______________________________________.
6 English start your time does class what usually
_______________________________________?
7 and I’m my journalist I a job like
_______________________________________.
3 Underline the correct word.
Example: What’s / Whats your name?
1 A What are this / these?
B They’re my house keys.
2 A Who’s that / she?
B My husband.
3 This is a / an English dictionary.
4 A Are those / that your books?
B No. My books are in my bag.
5 Your / You’re a good teacher!
6 A Are you OK?
B Yes, I’m / I am.
7 Oleg’s father is Russian, but he’s / his mother is French.
8 We don’t / doesn’t like pizza.

VOCABULARY
4 Tick (✓) A, B, or C to complete the sentences.
Example: Nice to ________ you.
A meet ✓ B hello C well
1 A Are you ________?
B Yes, I am.
A Egypt B Polish C Germany
2 A Do you ________ English?
B Yes.
A say B write C speak
3 Jack and Sue have four ________.
A child B childs C children
4 What ________ is it now?
A time B hour C o’clock
5 A Is Harry ________?
B Yes. His wife’s name is Clare.
A husband B married C single
6 A Where’s your sister?
B She’s ________ holiday in the USA now.
A in B to C on
7 Do you ________ coffee in the mornings?
A cook B drink C eat
8 I go ________ work at 7 o’clock.
A to B on C at
9 A Where’s Nick today?
B He’s in London on ________.
A business B work C office
10 Please ________ the window.
A stop B open C sit
11 A Is Carlos a teacher?
B I don’t ________.
A say B know C spell
12 A What’s your ________?
B It’s anna@write.uk.
A address B postcode C email address
13 I read ________ every weekend.
A TV B magazines C passports
14 A Where are your ________?
B In my bag.
A keys B houses C parents
15 I have a photo of my husband in my ________.
A credit card B purse C glasses
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25 - 5
50 – 30
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45​
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1. Берілген ұғымдарды мәнін ашып, сұраққа жауап беріңіз.
1
Қос дөңгелекті арба

2
Империя

3
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а,если V=2184 cм³,b=12 см,c=13 см
b,еслиV=9200 см³,a = 23 см, с = 25 см
ab,если V=1088 дм³,c=17 см
пожалуйста
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