x: 3 / 4 = 6:9 / 8

x: 3 / 4 = 6:9 / 8

x：3/4=6：9/8
9/8x=3/4X6
x=4

(3 / 4 + 1 / 5) + (4 / 5 + 1 / 6) + (5 / 6 + 1 / 7) + (6 / 7 + 1 / 8) + (7 / 8 + 1 / 9) =? Very urgent

It's only the beginning and the end. The score in the middle is easy to add. You can see it by removing the brackets

The number of a is 166 times larger than that of B, and the number of a is 14 times less than that of B. what are the numbers of a and B?

(166+14)÷(9-1)
=180÷8
=22.5
22.5+166=188.5

Let a be an M * n matrix with rank a = R, then AX = B has at most n – r linearly independent solutions?

No,
If AX = B has a solution, let α be a special solution,
Because there are n – r linearly independent solutions in the fundamental solution system of AX = 0, let
a1,a2,...,an-r
Then it is not difficult to prove that α, α + A1, α + A2,... α + an-r are N-R + 1 linearly independent solutions of non-homogeneous linear equations AX = B

A, B and C three workers work together to make a batch of parts. A processes 25 of the total number, 125 more than B, and the ratio of B to C is 3:2. How many parts are there in total?

3 + 2 = 5125 ^ [25 - (1-25) × 35], = 125 ^ [25 − 35 × 35], = 125 ^ [25-925], = 125 ^ 125, = 3125 (pieces); answer: there are 3125 pieces in this batch of parts

How to solve 36.5-7x = 4 (x + 5) equation

36.5-7x=4(x+5)
36.5-7x=4x+20
4x+7x=36.5-20
11x=16.5
x=16.5÷11
x=1.5

There are 1680 tons of warehouse A and warehouse B. It is known that 1 / 4 of warehouse A is equal to 1 / 3 of warehouse B. how many tons does warehouse a have

A: B = 4:3
A has 1680 × 4 △ (3 + 4) = 960
B has 1680 × 3 △ (3 + 4) = 840
Are you satisfied with the above answers?

There are 18 cases for each big car and 12 cases for each small car. At present, there are 18 cars worth 3024 yuan. If each box is 2 yuan cheaper, the goods are worth 2520 yuan. How many cars are there for each big car and small car?

According to "if each box is 2 yuan cheaper, then the value of this batch of goods is 2520 yuan", we can know that 3024-2520 yuan cheaper, this batch of goods has 504 ／ 2 = 252 cases. Suppose 18 cars are big cars, then 18 × 18 = 324 (cases), 324-252 = 72 cases more than the actual number of cases

Simple mathematical problems of fraction operation
Simple calculation: fraction
7 / 13 × 6 / 29 + 6 / 13 × 22 / 29

7/13×6/29＋6/13×22/29
＝（6/13＋1/13）×6/29＋6/13×22/29
＝6/13×（6/29＋22/29）＋1/13×6/29
＝6/13×（1－1/29）＋1/13×6/29
＝6/13×1－6/13×1/29＋（1/13×6）×（6/29÷6）
＝6/13

(1 / 2) 1. In the equal ratio sequence [an], A3 = 7, the first three terms and S3 = 21, then what is the value of common ratio q
(1 / 2) 1. In the equal ratio sequence [an], A3 = 7, the first three terms and S3 = 21, then what is the value of common ratio q?
2. In the equal ratio sequence [an] with the common ratio of integer, if a1 + A4 = 1

a3=a1*q^2=7
a1+a2=S3-a3=a1+a1*q=14
Division of two formulas: (1 + Q) / Q ^ 2 = 2
Q = 1 or - 1 / 2