(3 / 8 + 5 / 6) x = 870

(3/8+5/6)x=870
(9/24+20/24)x=870
29/24*x=870
x=870*24/29=720

RELATED INFORMATIONS

1. If two arithmetic sequences {an} {BN} satisfy a1 + A2 + a3 +. + an / B1 + B2 + B3 +. + BN = 7n + 2 / N + 3, find A5 / B5 I use two methods to calculate, the results are different... Help me see what's wrong with the second one The first type: (a1 + A2 + a3 +. + an) / (B1 + B2 + B3 +. + BN) = 7n + 2 / N + 3 San/Tbn=(7n+2)/(n+3) a5/b5=[1/2*(a1+a9)]/[1/2*(b1+b9)] =9*[1/2*(a1+a9)]/9*[1/2*(b1+b9)] =S9/T9 =(7*9+2)/(9+3) =65/12 The second type: a1 + A2 +... + an = 7 * n square + 2n; B1 + B2 +... + BN = n square + 3N Then A5 / B5 = 4.625
2. 3 (x + 1.7) = 9.6
3. Linear algebra. Let vector groups A1, A2, A3 be linearly independent, and find a maximal independent group of a1-a2, A2-A3, a3-a1
4. How many natural numbers from 1 to 1998 are squared by 72?
5. Vector Cartesian coordinates. Just learned, 1. Given that a = (1,2), B = (2,3), real numbers x, y satisfy the equation XA + Yb = (3,4), find x, y 2. Given points a (- 1,1), B (- 4,5) and vector BC = 3, vector Ba, vector ad = 3, vector AB, vector AE = 1 / 2, vector AB, find the coordinates of point c.d.e 3. Given that the distance between a point B and a (5,12) on x-axis is equal to 13, calculate the coordinates of point B 4. Given that the abscissa of P is 7 and the distance from point P to point n (- 1,5) is equal to 10, calculate the ordinate of point P
6. Factorization x ^ 4-8x ^ 2Y ^ 2 + 16y ^ 4
7. As shown in the figure, in the triangle ABC, the angle a is greater than 90 degrees, BD and CE are the heights of the triangle respectively, and M is the midpoint of the edge BC, connecting De, DM and em (1) Proof: Triangle MDE is isosceles triangle (2) Try to explore: whether the triangle MDE can become a right triangle, if possible, request the BAC degree of this angle, if not, please briefly explain the reason
8. Calculate the product (1-2 / 2) (1-3 / 2) (1-4 / 2) (1-1999 1 / 2) (1-2000 1 / 2) equals () A. 1999 / 2000 B. 2001 / 2000 C. 1999 of 4000 d.2001 of 4000
9. Looking at the figure below, the four points of ABCD on the number axis correspond to integers. If the digit a corresponding to point a, point B corresponding to B, and b-2a = 7 So which of a, B, C, D is the origin on the number axis? Explain the reason__ |__ |__ |__ |__ |__ |__ |__ |__ |__ |__ |__ |__ |_____ → A B C D
10. 2x-6x + 5 factorization factor x-3x-10 factorization factor
11. Find the value of x-3 of 6 = x + 5 of 8
12. How to solve 3 / 8: x = 5%: 0.6
13. Minus 0.36 times minus two ninths equals zero
14. (negative two thirds) × (- 18) + (+ 0.25) × (- 6) × (- 5)
15. Three parts equals eight parts equals one part equals 24 parts equals 0.25
16. 2 divided by 8 / 5 * 25 / 24 [1 - (1 / 2 + 1 / 3)] * 36
17. 3: 12 = 6 divided by 24 = 0.25 = 36 parts = ()%
18. Simplification 36:24 2:3:8.4:1.6 1:4 1 4:36 0.12:2.4 2:16 9
19. Simplification: (1) 3-18 (2) - 24-36 (3) - 24-6 (4) - 16-48
20. Simplification ratio 15:0.03 18:0.12 1:36 1 0.9:40 8.8:10 8:5:4 3 It's urgent