Предмет: Математика, автор: goida82

за 2 ч две учительницы проверяют 120 работ городской олимпиады по математике. Сколько работ проверят за это время трех учительницы, если будут работать с той же производительностью?

Ответы

Автор ответа: 45ВиКуСеНьКа45
0
120:2=60 работ проверили каждая  1 и 2 учительница за 2 часа
60*3=180 работ проверят 3 учительницы за 2 часа
Автор ответа: Diamondstina
0
1) 120:2=60 работ проверяют две учительницы за час
2) 60:2=30 работ проверяет за час одна учительница
3) 30•3=90 работ проверят три учительницы за час
4) 90•2=180 работ проверят три учительницы за два часа
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1)Choose the correct answer, A, B or C

1 Can you see that girl with ... hair?
A tall
B curly
C young
2 I'm sure Gary spends a lot of time in the gym. He's very ...
A ugly
B pretty
C sporty
3 My brother is a bit ... he finds it difficult to talk to people he doesn`t know.
A shy
B calm
C naive
4 Doris is a lot of fun. She's got a great ... of humour.
A sense
B model
C record
5 This ... is big, but it looks good on my head.
A tie
B hat
C jacket
6 Most people wear a ... to do sport.
A coat
B skirt
C tracksuit
7. What ... are you, medium or large?
A fit
B size
C label
8 We don't have to wear ... clothes on Fridays. We can come to the office in jeans and a T-shirt.
A smart
B untidy
C organic
9 Excuse me, can I try these trousers ... ?
A on
B in
C up
10 l'd like to ... in love and get married before I finish university.
A fall
B drop
C break

2) Complete the words. Write one letter in each gap.

1 You need a t..... too speak and taste food. It's inside your mouth.
2 A person who hasn't got any hair is b...
3 Aperson who has a lot of things to do is very b...
4 A d... is a situation when you go out with your boyfriend or girfriend.
5 A w.. is hair to wear on your head that is not your Own.
6 An e....... is the situation when people vote for a new government etc.
7 A m.. idea is completely crazy.
8 An u......... person doesn't like being with other people or going to parties.
9 Blond and light brown hair is f...
10 You wear s.... on your feet inside your shoes or boots.

3 Complete the sentences with the words in the box.

changing room, forehead, middle-aged, comfortable, identity card, quality, confident, make-up, twins, scarf .

1 This dress is very cheap but it's not good ...
2 Students can't wear ... at my school.
3 Put on your hat and ... and let's go for a walk in the snow.
4 Wash your face - your ... is dirty.
5 My sisters are .... They`re ten today.
6 These shoes are very ....
7 To get a tattoo, you need to have an ... which shows that you're eighteen.
8 It can be difficult for .... people to find a job.
9 I want to try on this T-shirt – where's the ...?
10 Henry is very .... and thinks he will win the race easily.