Knowledge points and exercises of the first volume of fourth-grade mathematics "Understanding of Large Numbers" published by People's Education Press.

# 4th grade # Introduction Understanding of Large Numbers is the initial unit of the first volume of the fourth grade mathematics textbook, which is based on students' understanding and mastery of numbers within 10,000. Large numbers exist widely in life. Understanding large numbers is not only the consolidation and expansion of reading and writing numbers within ten thousand, but also one of the most basic mathematical knowledge that students must master. I have prepared the following contents for you, hoping to help you.

Knowledge points of Understanding Large Numbers, the first volume of fourth-grade mathematics published by People's Education Press.

1.1010,000 is 100,000,1010,000 is 1 million,101 million is 10 million,1010 million is 100 million. The advance rate between every two adjacent counting units is "10". This counting method is called decimal counting method.

Special attention: the difference between counting units and numbers.

2. When using numbers to represent numbers, these counting units should be arranged in a certain order, and their positions are called numbers.

3. Number of digits: A number contains several digits, that is, several digits. For example, 652 100 is a six-digit number.

According to our country's counting habit, every four digits are counted from the right.

5. How to pronounce hundreds of millions or more:

(1) Grading first, starting from high reading. Read level 100 million, then level 10,000, and finally level 1.

(2) Billions should be read according to the pronunciation of billions, and then the word "billion" should be added at the end. Ten thousand series should be read according to the reading method of ten thousand series, and then the word "ten thousand" should be added after it.

No matter how many zeros there are at the end of each level, don't read them. Other numbers have a "0" or several "0" in succession, all of which are read only.

6, hundreds of millions of words:

(1) Write from bits, first write 100 million levels, then write 10,000 levels, and finally write one level.

(2) If there is no unit, just write 0 on the number.

7, compare the size of the quantity:

The two numbers are different, the one with more numbers is bigger and the one with fewer numbers is smaller.

(2) Two numbers with the same number of digits, starting from the number of digits, the number with the largest number of digits is larger. If the numbers on the numbers are the same, compare the numbers on the next number until the size is compared.

8. Number of rewrites:

Rewrite it into a number in the unit of "10000" or "10000000". Draw a grading line first, divide the integer 10 thousand or integer 100 thousand into four levels, then omit four zeros from each level and replace them with the word "100 thousand"

9. Find out the approximate figures:

The mantissa after omitting ten thousand digits depends on the number on one thousand digits; The mantissa after omitting 1 100 million bits depends on the number on1100 million bits.

When calculating the divisor by "rounding", it depends on whether the number of the omitted mantissa part is less than 5 or equal to or greater than 5. If it is less than 5, the mantissa is discarded and rewritten as a corresponding number of zeros; If it is equal to or greater than 5, advance 1, then discard the mantissa and rewrite it as a corresponding number of zeros.

10, indicating the number of objects: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ... are all natural numbers. There is no object, which is represented by 0, and 0 is also a natural number. All natural numbers are integers.

1 1, the smallest natural number is 0, there is no natural number, and the number of natural numbers is infinite.

12, calculator ON/CE: switch the clear screen key to clear the contents on the display screen.

AC: Clear the key, clear everything.

DEL: Clear the wrong number or operation symbol just entered.

13. On the abacus, 1 upper bead stands for 5, 1 lower bead stands for 1.

Two-person education edition fourth grade first volume mathematics "understanding of large numbers" exercises.

1. Fill in the blanks. (1) 10 One thousand is (), 10 Ten thousand is ().

(2) The digits adjacent to 10,000 digits are () and (), and the digits adjacent to 100 million digits are () and ().

(3)5030600 is () digit, 5 is () digit, indicating () digit, 3 is () digit, indicating () digit, and 6 is () digit, indicating () digit.

(4) Thirty-four million two hundred and nine thousand is a number (), written as (), and the mantissa after omitting ten thousand is about () ten thousand.

(5) The total grain output of a city is 20 123 1900000 kg, and the mantissa after omitting 123 19000000 is about () billion.

2. Judge whether the following statement is correct.

(1) One billion bits The right digit is one billion bits, and the left digit is ten million bits. ( )

(2) The number of billions is 10. ( )

(3) The smallest natural number is 1. ( )

(4) 3854000000 ≈ 400 million. ( )

(5) On the abacus, 1 upper bead means 5, 1 lower bead means 1. ( )

3. Read and write.

1. China covers an area of about 9.6 million square kilometers.

9.6 million writing ().

2.2065438+In the first quarter of 2007, the sales volume of a certain brand of mobile phones was 420724.

420724 is pronounced ().

3.20 16 tmall double eleven sales reached 1000000000 yuan.

1000000000 is pronounced as ().

4.20 16 China census is 13827 1 100 million people.

13.827 1 100 million writing ().

4. Compare the sizes of each group below.

32700( ) 124300 62 147( )543 12

43 159( )43 178 374200( )374 189

5. Rewrite the numbers and find the divisor.

360000= () ten thousand

23 million = () ten thousand

50000000000 = () billion

35 124≈ () ten thousand

93423 1≈ () million

789004002≈ () billion

Intransitive verbs solve problems.

1. Use the five numbers of 0.2.4.7.8 to form a five-digit number, so the mantissa after omitting 10,000 is about 80,000. What's the five-digit number? What's the minimum?

2. Xiaohong copied a six-digit number, misspelled the seven-digit number as 1, and misspelled the zero-digit number as 6. How much smaller is the new number than the original six digits?

Reference answer

I. 65438+100000 yuan

2. Thousands, hundreds, thousands, billions.

37 million, 51 million, 31 million, 61 million.

4.8 34209000 342 1 ten thousand

5 1.23 billion

( 1) × (2) √ (3) × (4) × (5) √

1.96000 2

3 3. 10/000 million 4 1387 10000

Four.

V.36 2300 5 4 93 8

6. 1. This five-digit number is 84720. The lowest is 78024.

2. Write 7 errors in 1 00000 bits as1,which is 600000 less than the original number, and write 0 errors in 100 bits as 6, which is 600 more than the original number. Subtract these two numbers to get the desired number. 600000-600=599400

Three-person education printing plate fourth grade first volume mathematics "understanding of large numbers" exercise.

Fill in the blanks. (2 points for each space, ***40 points) The London Olympic Organizing Committee estimates that 1 and 20 12 can arrange about 6.6 million Olympic tickets, which will be available for sale from 20 1 1. 6600000 is pronounced (). It is () digits, the first "6" from the left means () (), and the second "6" means () ().

2. Ten thousand is () one hundred, 100 () is one hundred million, and one thousand is () ten thousand in Wan Li.

3. Tens of millions of digits are () digits, and seven digits are () digits.

4. The unit of a number is 8, and all other digits are 0. This number is written as ().

5. A natural number rounded to 10,000 digits is 200,000, this number is (), and the minimum value is ().

6. Write the number as required.

China is one of the countries with the most serious soil erosion in the world. The latest data show that China's existing soil erosion area is 3.56 million square kilometers, accounting for 37% of the country's land area; The total amount of soil lost every year is 4.998 billion tons, which brings multiple hazards to society, economy, people's production and ecological security.

(1) 3.56 million square kilometers, writing () square kilometers.

(2) 4,998,000,000 tons, omitting the mantissa after the digit 1 billion, which is about () tons.

(2) By the end of 20 1 1, the number of people participating in the new rural cooperative medical system in China had reached 832 million. The number on the horizontal line was written as (), and the mantissa after omitting the digits of 1 billion was about () billion.

(3) Read the numbers on the horizontal line.

The China Pavilion of the Shanghai World Expo has a building area of 105879 square meters, and the structural system is a steel frame-shear wall structure system, with a steel consumption of 23,000 tons. ① 105879 square meters is pronounced as () square meters. ② 23,000 tons is pronounced as () tons.

Second, judge. (For drawing "√" or wrongly drawing "×", 2 points for each question, *** 10)

1, 303006950 Reading: 303069500. ( )

2. The digits adjacent to the tens of thousands are thousands and hundreds of thousands. ( )

All seven digits are less than eight digits. ( )

4.895004000 ≈ 8.9 billion. ( )

5. Upper and lower bead devices of abacus device 5 1. ( )

Third, choose. (Fill in the correct serial number in brackets, 2 points for each question, *** 10)

1, among the following numbers, the number that does not read 0 is ().

a、93000006 B、9030600 C、93006000

2. The smallest natural number is ().

A, 0 B, 1 C, none

3. 17□763≈ 180000, and the minimum () is □.

a、4 B、5 C、9

4. Write in the unit of "100 million", the approximate number is 2 billion, and the number is ().

a、 1945967000 B、200000000 C、2045309000

5, in the process of calculation, if you find that the input data is incorrect, use the () key to clear the error.

a、MC B、CE C 、=

4. Arrange the following figures in descending order. (5 points)

759600 907056 700596 90576 706509

Fifth, solve the problem. (Each question 10, ***30)

Nine digits consisting of 1 and 1, 2, 3, 4, 5, 6, 7, 8, 9 are about 900 million after rounding. What are the minimum and nine digits?

(1) is: ()

(2) Minimum: ()

2. What's the six-digit number? What's the smallest six digits? What's the difference between them?

(1) is: ()

(2) Minimum: ()

3. The password consists of nine digits, the digits and millions of digits of this number are the smallest counting units, the digits of tens and millions are 60, the digits of hundredths are 3 less than the smallest natural number, the digits of thousands and tens are 5 more than the smallest natural number, and the digits of the other two digits are 8. Can you guess what the password is?

The password is: ()

Sixth, the problem of thinking expansion. (5 points)

Use 6 "9s" and 6 "0s" to form a twelve-digit number that meets the following requirements. (Just write one)

(1) Don't read any zeros: (). (2) Read only a zero: ().

(3) Read two zeros: (). (4) Read three zeros: ().

(5) Read four zeros: ().

Reference answer:

One,

1 6.6 million 76.6 million

2, 100 10 10 1

3.8 million

4、800080008