The study of quantity begins with numbers. At first, it begins with the familiar natural numbers and integers, as well as the rational numbers and irrational numbers described in arithmetic. The following is the answer to my second grade math homework in summer vacation. I hope everyone will read it carefully!
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3. 1, 18+ 16-9=25 (person) 2,3? 8+9=33 (Ben)
3、 10? 5=2 (pieces) 10? 2=5 (person)
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2. Right angle: 1, 6 acute angle: 3, 5 obtuse angle: 1, 4.
Third, translate all three vertices of the triangle to the left by 9 squares, and then connect them.
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One, two, (3) right angles, (3) acute angles and (1) obtuse angles. 3、3,6,2
Second, 1, 18? 3=6 (yuan) 5? 6=30 yuan 2, (1)63? 9=7
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Second, kilograms, grams, kilograms. (1)100g (2) 200g (3) 400g
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3. 1, 800+200 =1000 2,35? 5=7 3、 1500-800=700
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First, look at the questions carefully, circle first and then calculate. 18? 6=3 (total? Number of copies = number of copies)
Second, 1,? 2、? 3、? 4、?
Third, 1, 6? 4=24 (piece) 24+25=49 (piece) or 6? 4+25=49 (piece)
2、6? 3= 18 (block) 18? 2=9 (block) or 6? 3? 2=9 (block)
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1. 1, 4, 6, 16, 24, 4 2, 30, 15, 40 (continuous decrease, or sum of two numbers in the total)
Two, two? 2=4 (tree) (before allocation to white rabbits) 4? 2=8 (tree) (before lamb is divided)
8? 2= 16 (tree)
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2. 1, 1 2,33,1,4? 9=36 (person) 36? 6=6 (person) (can also be integrated)
2. 18+ 14=32 (flower) 32? 4=8 (flower) or (18+ 14)? 4=8 (flowers)
Note: The column synthesis formula must be enclosed in brackets.
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Two, 1, 30032,60504, Gao, Qian, 1, do not read.
3. 1, 700+700 =1400 2,54? 9=6 3、 1000- 100=900
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First hint: look at the size before queuing.
1、2068、286、2608、2806、2860
2、5550、5505、5500、5055、5005
3、8? 7、6? 6、8 1? 9、40? 5、35? five
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Note: the students in this question can't investigate the statistical data at home, so please ask the teacher to give the data.
Students do the questions according to the data I gave them. From beginning to end: 7, 4, 3, 1 1, 9.
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Second, 1,? 2、? 3、? 4、?
Three. 1, 90-(45+25)=20 (piece) or 90-45-25=20 (piece)
2、 12? 4? 8=24 (yuan) (it can also be calculated step by step)
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Third, 1,? 2、? 3、? 4、?
Iv. 1 company ③, 2 company ①, 3 company ②
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1.1,44+77 =1212. Put any two of the four corners in the middle.
Two, six, nine, 12 three, 1 2? 6? 4=3 (piece) 2,52-11+15 = 56 (piece)
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I. 1, 32, 23, 24, 35, ②
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Second, 1,? 2、? 3、? 4、?
Fourth, 1, 45? 9=5 (pieces) (select relevant conditional expression) 2,310-130 =180 (Ben)
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Iv. 1, 320+ 170=490 (yuan) 490
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1. 1, up 2, right 6 or right 6 up 2.
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4. 1, 120-40=80 (tree) 2,40? 8=5
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One, two, sunspot, the last one in the first row, and the third one in the third row of albino stars.
(The movement of the column is 1, 2,3, and the row is 2,3, 1).
2.4+3+2+ 1= 10 angles.
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Two, 600,800,999, 10000 three, 1 56? 8 = 7 2,85-60+65 = 90 (pieces)
3、5? 2+5= 15 (pieces)
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One, five, 10, two, five three, 600, 300, 700, 270, 600, 220.
4.3 1, 2? 3=6 (tablets) 18? 6=3 (days)
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Fourth, 1, 8? 4=2
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2, 137, 146, 155 3, 18 (plus 1, 2, 3, 4, 5. . . ) rule
4,31(Law of 2,4,6,8, 10, 12)
Third, 1, 9? 9= 1 2, 690-390=300 4, 1, 3, 4
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Two, two, two, two, three, 1, 48? 8=6 (platoon) 2,28+36-40 =14 (head)
3、3? 6-9=9 (branch)
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1. 1, 22, 22. No one is right. Sheep can pay 100 yuan to wolves.
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Second, 1, the law of shifting the tail of the first picture. 2. The last rule to move to the front.
3. Right turn law.
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Three, 1, 32, 33, 24, 25, ①
① Four, 40-3? 8= 16 (piece)
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Third, 1, 2? 8? 4=4 (pieces) 2, (40- 10)? 6=5 (pieces) (step by step)
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1、500-360= 140 2、72? 9=8 3、 100+900= 1000
Iii. 12? 6? 7= 14 (yuan)
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One, six, five, four, two, three+two+1 = 6 (each repeating group has six balloons).
16? 6=2 (group) There are 4 left, and the fourth is a yellow balloon. Third, Xiaodong is right.
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1. 1, 100.2、5000、500 1、5002、5003、5004。 3、 1200。
4、28? 4、72? 9 、54? 6 、2? 9、4? eight
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Ii. 1, 32, 33, 24, ①
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Fourth, 1, 8? 7+36=92 (page)
2.480-290= 190 (only) Note: Find out the quantity related to the problem.
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1. 1, 36? 9 = 4 2,50-36 =14 (years old) 9+ 14=23 (years old)
Second, analysis: first determine the number of adults and children in the whole family to calculate the fare, excluding the elderly over 60 years old.
Grade 3, Grade 15, Grade 26, Grade 34.
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Second, 1, (1) Find the total by multiplication. (2) Find each share by division and formulate it with known conditions.
2, 4 3, 1, (32-8)? 6=4 (pieces) 2, 15-2+ 15=28 (pieces)
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1 .kg, g, cm and m. (Distinguish length units from mass units)
Third, look at the order of demand from small to large, and connect with less than sign in the middle.
4. 12? 4=3 (meter) Analysis: Fold it twice, and then break it into four sections.
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Four, 27, 400, 40
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One, four, eight, four (first, the left is equal to 17, and the maximum value on the right is 16, so fill in 4).
10 (the right is equal to 28 and the left is 27, so fill in 10.
Third, 1, 8? 3? 6=4 (block) 2,9? 8-56= 16 (pieces) 3,24? (2? 3)=4 (branch)
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Second, the laws of 1 and -9. 2. Add 1, 2, 3, 4. . . Law.
3. Add 2,4,6,8, 10. . . Law. 4. Divide by 2.
Third, 1, 5? 2+24=34 (yuan) 2, 12? 6-2
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I.1600,3200
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Third, 1,? 2、? 3、? 4、? 5、? 6、?
4. 1, 21-15+9 =15 (only) 2, 12? 6=2 (6+ 12)? 2=9 (bar)
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2. 1，80-23- 17 = 40(m)80-(23+ 17)= 40(m)
2、4? 6+27=5 1 (branch)
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