theere are two taps pouring water into a tank. tap a can fill up the tank in 23 minutes, tap b can fill the tank in 16 minutes. if tap a is opened first, how many minutes later should tap b opened in order for the amount of water form tap a double that from tap b when the tank is full
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Một rectanglar tank is 50 cm long, 40cm wide and 45cm hight. The height of the water level in the container is 15cm. How many more litres of water are required to the fill up the tank completely?
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bể hình chữ nhật Một là dài 50 cm, 40cm và rộng 45cm cao.
Chiều cao của mực nước trong container là 15cm
. Làm thế nào nhiều hơn lít nước được yêu cầu phải điền lên xe tăng hoàn toàn?
bài như vậy à
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Chiều cao của bể là 45 cm mà hiện tại mực nước của bể chỉ cao 15 cm.
Nên chiều cao của số phần nước chưa có trong bể là :
45 - 15 = 30 ( cm )
Muốn tìm được số l nước cần đổ thêm ta lấy dài x rộng x cao: ( chú ý : đơn vị phải là dm khối )
(=) 50 x 40 x 30 = 60 000 ( cm khối ) = 60 dm khối = 60 lít nước ( do 1 dm khối = 1 lít nước )
Vậy số lít nước cần đổ thêm là 60 lít nước
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1/ The average height of 2 boys is 131.6cm . The average height of 4 girls is 128.3cm . What is the average height of all children ? Answer : ....... cm 2/ Two years ago . Miss Lans salary was $2300 . She got a 5% increment last year and a 10% increment this year . What is Miss Lans salary now ?Answer : $ ...... ?3/ A rectanglar tank is 50cm long , 40cm wide and 45cm high . The height of the water level in the container is 15cm . How many more litres of water are roquired to fill up the tank com...
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1/ The average height of 2 boys is 131.6cm . The average height of 4 girls is 128.3cm . What is the average height of all children ?
Answer : ....... cm
2/ Two years ago . Miss Lan's salary was $2300 . She got a 5% increment last year and a 10% increment this year . What is Miss Lan's salary now ?
Answer : $ ...... ?
3/ A rectanglar tank is 50cm long , 40cm wide and 45cm high . The height of the water level in the container is 15cm . How many more litres of water are roquired to fill up the tank compietely ?
Answer : ............. l
Pool A rectangular shape with a length 19,2m.Neu Rock, 22.5 width 414,72m cubic tank, the water level in the tank up to four-fifths of the height of the height of the tank be.Hoi how many meters?
A rectangular tank, measure 40 cm by 38 cm with a height of 30, is filled with water to a height of 10 cm.
a, Find the volume of water in the tank.
b, When 5 indentical iron balls are dropped into the tank, the water level increases to half of the tank. Find the volume of each iron ball.( giải bằng tiếng anh giúp! ><)
The volume of water in the tank :
40 x 38 x 10 = 15200 cm3
The volume of each iron ball is :
(40 x 38 x ( 30 : 2 ) -15200 ):5=1520 ( cm3 )
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Choose the word or phrase among A, B, C or D that best fits the blank space in the following passage.Seventy percent of people in Viet Nam live in rural areas. Most of these people (1)……. their living by caring for farm animals like pigs. Other common jobs are crop fanning and fishing. For many of these farmers and fishermen, animal and plant waste is still a problem.Many women and children cook meals using traditional cooking fuels. They also spend many hours (2)………wood and other materials to b...
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Choose the word or phrase among A, B, C or D that best fits the blank space in the following passage.
Seventy percent of people in Viet Nam live in rural areas. Most of these people (1)……. their living by caring for farm animals like pigs. Other common jobs are crop fanning and fishing. For many of these farmers and fishermen, animal and plant waste is still a problem.
Many women and children cook meals using traditional cooking fuels. They also spend many hours (2)………wood and other materials to burn. This process takes time and also uses a lot of natural resources. Moreover, they suffer the same health (3)……... Cooking was a difficult and dangerous job. The kitchen was smoky, and the black ash would make people cough, and (4)………. pain in the eyes.
But a biogas system can (5)………all of these problems! It can turn animal or plant waste (6)…….valuable resources - such as cooking fuel, electricity and plant fertilizer. First, an expert must build a system of pipes and tanks. This biogas system contains and manages the decaying process of animal or plant waste. To use the biogas system, a fanner must move animal waste into a pipe with water. These pipes bring the waste to a tank (7)……..in the ground. This tank is called a bio-digester. Air cannot enter this tank. In this contained environment, natural bacteria decays the waste material. (8)……..the waste decays in the bio-digester, it (9)…….two things - biogas and slurry. The biogas rises to the top of the tank. The pressure from the gas pushes the liquid slurry into (10)……. Now people can use both the biogas and the slurry.
Question 1
A.earn
B.look for
C.do
D.take
Đáp án: A
Earn a living (v) kiếm sống
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Read about the landmarks. Can you guess which landmark from 1 they are? ( Đọc về các địa điểm sau. Bạn có thể đoán được chúng là gì không?)It is the most famous tower in England. The name is often used to describe the tower, the clock and the bell in the tower. The bell is the largest bell ever made in England.1. ______________Danish architect Jorn Utzon designed the place, and Queen Elizabeth II opened it in 1973. It is a UNESCO World Heritage building.2. ______________One of Hanois most well-k...
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Read about the landmarks. Can you guess which landmark from 1 they are? ( Đọc về các địa điểm sau. Bạn có thể đoán được chúng là gì không?)It is the most famous tower in England. The name is often used to describe the tower, the clock and the bell in the tower. The bell is the largest bell ever made in England.1. ______________Danish architect Jorn Utzon designed the place, and Queen Elizabeth II opened it in 1973. It is a UNESCO World Heritage building.2. ______________One of Hanoi's most well-known landmarks, this place was built in 1070. It is next to Quoc Tu Giam, Viet Nam's first university.3. ______________Gustave Eiffel designed this tower in 1889. Now, almost 7 million visitors visit it a year.That makes it the most visited landmark in the world.4. ______________A creature with the head of a lion and the body of a fish, it is the symbol of Singapore.5. ______________
1.Big Ben
2.Sydney Opera House
3.Temple of Literature
4.Eiffel Tower
5.Merlion
In order to increase the volume of a cuboid tank, peole increase the length of the tank and keep the width and the height unchanged. The area of the base increases by 75% and the tank can contain 1500 more liters of water. Find the volume of the tank before change?
In order to increase the volume of a cuboid tank , people increase the length of the tank and keep the width nd the height unchanged . The area of the base increase by 75% and the tank can contain 1500 more liters of water . Find the volume of the tank before change?
In order to increase the volume of a cuboid tank, people increase the length of the tank and keep the width and the height unchanged. The area of the base increases by 75 % and the tank can contain 1500 more liters of water. Find the volume of the tank before change ?