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There are 49 students in class one of grade five. Five eighths of the known number of girls is equal to 60% of the number of boys Please hurry up
5 / 8 of girls equals 60% of boys
Boys equal to girls: 5 / 8 △ 60% = 25 / 24
Female students: 49 (1 + 25 / 24) = 24
Male: 49-24 = 25
If there are two real roots of the quadratic equation X2 (the square of x) + 4x + 2K = 0 with respect to x, find the value range of K and the non negative integer value of K
Urgent request!
X^2+4x+2k=0
b^2-4ac=16-4*2k≥0
16-8k≥0
k≤2
Non negative integer value 0 1 2
In a class, there are two girls less than two fifths of the class, and 22 boys. How many students are there in the class?
Are there any boys and girls in the class? Is there anyone who is not an integer? Otherwise, it can't be calculated
Addition and subtraction of square root
（1）.（√12-√4/3）-2(√1/8-1/√2-√18)
(2) . & sup3; √ 01.125 - √ 3 and 1 / 16 + & sup3; √ (1-7 / 8) & sup2;
（3）.（√7+√3）（√7-√3）-√16
（4）.（2√2+3）^2008（2√2-3）^2009-4√1/8-2/√2
(5) . absolute value - √ 2 + absolute value √ 2 - √ 3 - absolute value 2 - √ 3 - √ 3 / 2
1. = (2 √ 3-2 √ 3 / 3) - 2 (√ 2 / 4 - √ 2 / 2-3 √ 2) = 4 √ 3 / 3-2 (- 13 √ 2 / 4) = 4 √ 3 / 3 + 13 √ 2 / 22. & sup3; √ 01.125 is & sup3; √ 0.125? If so, = & sup3; √ 1 / 8 - √ 49 / 16 + & sup3; √ 1 / 64 = 1 / 2-7 / 4 + 1 / 4 = - 13. = (√ 7) ^ 2 - (√ 3) ^ 2-4 = 04. = [(2 √ 2 + 3) (2
The teacher gives something to a, B and C. two thirds of a is equal to two fifths of B and four fifths of C. It is known that the teacher has 250 requests for each of a, B and C
A: B = 2: (5 / 2) = 4:5 = 8:10 A: C = 2: (7 / 4) = 8: = 7 so a: B: C = 8:10:7 A: 250 △ 8 (8 + 10 + 7) X8 = 80 B: 250 △ 8 + 10 + 7 x10 = 100 C: 250-80-100 = 70 if you don't understand, please continue to ask
After moving the decimal point of a number to the right by two digits, the number obtained is 9.9 larger than the original number. What is the original number?
Let's assume that the decimal point of the original digit x is shifted to the right by two places, and then it is 100x. From the meaning of the question, we can list the equation as 100x-x = 9.9, and solve the equation to get x = 0.1, so the original number is 0.1
The ratio of number a to number B is 3:4, the ratio of number B to number C is 6:7, what is the ratio of number a to number C? Number a to number B
The ratio of number a to number B is 3:4, and the ratio of number B to number C is 6:7. What is the ratio of number a to number C?
9：14
If the equation sin ^ 2x-2sinx-a = 0 has a solution on X ∈ R, then the value range of a is?
I have a poor foundation,
Let t = SiNx t ∈ [- 1,1]
t^2-2t-a=0
The equation has a solution condition: B ^ 2-4ac > = 0
So 4 + 4 * a > = 0, a > = - 1
The root of the equation should be between positive and negative 1. The range of a and the intersection of the above formula should be solved
-1
6 / 5 of a number is 120. What's the number
Hehe, I don't want to draft
120 divided by 6 / 5 = 120 * 5 / 6 = 100
According to the program shown in Fig. 1, the function image of Y and X is obtained, as shown in Fig. 2. If the point m is any point on the positive half axis of Y axis, the intersection image of PQ ∥ X axis is made at the point P, Q and connected with OP, OQ through the point m, then the following conclusions are obtained: ① when x ＜ 0, y = 2x. ② the area of △ OPQ is a fixed value. ③ when x ＞ 0, y increases with the increase of X. ④ MQ = 2pm; &Nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp;, among them, the correct conclusions are as follows______ Fill in all the conclusions you think are correct
① When x < 0, y = - 2x, y = 4x, let P (a, b), q (C, d), then AB = - 2, CD = 4, and the area of △ OPQ is 12 (- a) B + 12CD = 3, so this option is correct. When x > 0, y = 4x = 4 · 1X, y decreases with the increase of X
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