Average application! There are two corn fields with an average yield of 450 kg / mu. The first field is 19 mu with an average yield of 430 kg / mu, and the second field is 497.5 kg / mu. How many Mu is there in the second field

Average application! There are two corn fields with an average yield of 450 kg / mu. The first field is 19 mu with an average yield of 430 kg / mu, and the second field is 497.5 kg / mu. How many Mu is there in the second field

The total yield of each plot is less than the average level: (450-430) * 19 = 380kg
The second plot is more productive than the average level: 497.5-450 = 47.5kg
The second plot: 380 / 47.5 = 8 mu

An average application problem!
When someone climbs the mountain, he travels an average of 4 kilometers per hour. After 5.5 hours, he reaches the top of the mountain and returns from the original road. After 4.5 hours, he reaches the original starting point. Find the average speed when he climbs the mountain

First calculate the distance up the mountain: 4 * 5.5 = 22 km
The total distance is 44 kilometers
The total distance divided by the total time is the average speed
44 / (5.5 + 4.5) = 4.4 km / h

Find an average problem
The store will mix 5 kg milk sugar of 10.02 yuan per kilogram, 3 kg fruit sugar of 5.54 yuan per kilogram and some crisp sugar of 6.74 yuan per kilogram to make a mixed sugar of 8.02 yuan per kilogram, which needs thousands of grams of crisp sugar?

（10.02*5+5.54*3+6.74*X）=8.02*(8+X)→X=0.02

An applied problem about the average
The store mixed 32 kg of crisp sugar and 20 kg of fruit sugar into assorted sugar, 19 yuan per kg of crisp sugar and 14 yuan per kg of fruit sugar. How much yuan should be sold per kg of assorted sugar?
There should be formulas, not direct answers, not equations

Total price of assorted sugar: 32 * 19 + 20 * 14 = 888 yuan
Total mass of assorted sugar: 20 + 32 = 52 kg
So the price per kilogram: 888 / 52 = 17.08 yuan

The application of integral in grade one of junior high school
Given a = a ^ 2 + B ^ 2-C ^ 2, B = - 4A ^ 2 + 2B ^ 2 + 3C ^ 2, and a + B + C = 0, find the polynomial C

Integral addition and subtraction + answers, 60 questions,

26 -6 -64 = 20 -64 = -44
27 + 3 -48 = 30 -48 = -18
28 + 12 -32 = 40 -32 = 8
29 + 21 -16 = 50 -16 = 34
30 + 30 + 0 = 60 + 0 = 60
31 + 39 + 16 = 70 + 16 = 86
32 + 48 + 32 = 80 + 32 = 112
33 + 57 + 48 = 90 + 48 = 138
34 + 66 + 64 = 100 + 64 = 164
35 + 75 + 80 = 110 + 80 = 190
36 + 84 + 96 = 120 + 96 = 216
37 + 93 + 112 = 130 + 112 = 242
38 + 102 + 128 = 140 + 128 = 268
39 + 111 + 144 = 150 + 144 = 294
40 -30 -140 = 10 -140 = -130
41 -21 -124 = 20 -124 = -104
42 -12 -108 = 30 -108 = -78
43 -3 -92 = 40 -92 = -52
44 + 6 -76 = 50 -76 = -26
45 + 15 -60 = 60 -60 = 0
46 + 24 -44 = 70 -44 = 26
47 + 33 -28 = 80 -28 = 52
48 + 42 -12 = 90 -12 = 78
49 + 51 + 4 = 100 + 4 = 104
50 + 60 + 20 = 110 + 20 = 130
51 + 69 + 36 = 120 + 36 = 156
52 + 78 + 52 = 130 + 52 = 182
53 + 87 + 68 = 140 + 68 = 208
54 + 96 + 84 = 150 + 84 = 234
55 -45 -200 = 10 -200 = -190
56 -36 -184 = 20 -184 = -164
57 -27 -168 = 30 -168 = -138
58 -18 -152 = 40 -152 = -112
59 -9 -136 = 50 -136 = -86
60 + 0 -120 = 60 -120 = -60
61 + 9 -104 = 70 -104 = -34
62 + 18 -88 = 80 -88 = -8
63 + 27 -72 = 90 -72 = 18
64 + 36 -56 = 100 -56 = 44
65 + 45 -40 = 110 -40 = 70
66 + 54 -24 = 120 -24 = 96
67 + 63 -8 = 130 -8 = 122
68 + 72 + 8 = 140 + 8 = 148
69 + 81 + 24 = 150 + 24 = 174
70 -60 -260 = 10 -260 = -250
71 -51 -244 = 20 -244 = -224
72 -42 -228 = 30 -228 = -198
73 -33 -212 = 40 -212 = -172
74 -24 -196 = 50 -196 = -146

Integral addition and subtraction calculation question 100, best with answers
First day of junior high school

85、(－3ab)2·（－2ab2）； 86、x(x－y)+x(y－x)； 87、(x+2)(x+3)； 88、(x－2)(x+3)；89、(x+2)(x－3)； 90、(x－2)(x－3)；91、(3a－4b)(2a－5b) 92、(x+2y)(x－2y)93、(5x－4y)(2x－3y) 94、(3x+4y)(3x－4y)95...

20 questions about integral addition and subtraction

1.3ab-4ab+8ab-7ab+ab=______ ． 2．7x-(5x-5y)-y=______ ． 3．23a3bc2-15ab2c+8abc-24a3bc2-8abc=______ ． 4．-7x2+6x+13x2-4x-5x2=______ ． 5．2y+(-2y+5)-(3y+2)＝______ ． 6．(2x2-3xy+4y2)+(x2+2xy-3y2)=______ ...

The addition and subtraction of the integral of a calculation question
If a ^ 3 + B ^ 3 = 35 and a ^ 2 · b-ab ^ 2 = - 6, what is the value of (a ^ 3-B ^ 3) + (3AB ^ 2-A ^ 2 · b) - 2 (AB ^ 2-B ^ 3)?

To solve the problem of integral calculation in the first day of junior high school,
Note: there should be multiplication of the same base power, power and product, division of the same base power, integral multiplication, square difference formula, complete square formula, integral division. It should not be too simple. Typing may be a little tired, so it's better to have more questions,

1. (- 2A) (1 / 4A & # - 1) 2, (- 1-2a) (2a-1) - 13, 298 square - 297 times 2994, known (a-b) square = 4, ab = 1 / 2, then (a + b) square = 5, known (M + 2n + 2) (M + 2n-2) = 12, then (M + 2n) square = (Chapter 1 operation of integers) unit test volume 2012 (2): (1