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The ratio of a, B and C is 1:2:3. The average number of a, B and C is 120. What are the numbers of a, B and C?
120 × 3 = 360, 1 + 2 + 3 + = 6360 × 16 = 60; 360 × 26 = 120; 360 × 36 = 180; answer: number a is 60, number B is 120, number C is 180
Miss Liu, what's the difference between finding the general solution of the matrix equation AX = 0 and the system of linear equations AX = 0?
X is not necessarily a column vector in a matrix equation
In general, a is reversible
In the system of linear equations AX = 0, X is a column vector composed of unknown variables
It is known that the working efficiency of Party A is 25% higher than that of Party B, so it takes half an hour less for Party A to process 200 machine parts than for Party B to process 180 machine parts
Let's suppose that it takes x hours for Party B to process a part, and the working efficiency of Party B is 1 / X
A's work efficiency = (1 / x) * (1 + 25%) = 5 / 4x
It takes 4 x / 5 hours for a to process a part
From the meaning of the title:
200*4x/5 +0.5 =180*x
20x=0.5
x=1/40
Then B processes 40 parts in an hour
A processes 50 parts per hour
（1）2x+3-2(x+5)=x （2）2（2x-1）-（x-3）=1 （3）8x-2（1-x）=7x-3（x-1） (4)2(10-0.5y）=-（1.5y-2)
There should be every step of the process
（1）2x+3-2(x+5)=x （2）2（2x-1）-（x-3）=1 （3）8x-2（1-x）=7x-3（x-1）2x+3-2x-10=x 4x-2-x+3=1 10x-2=4x+3-7=x x=0 x=5/6(4)2(10-0.5y）=-（1.5y-2)20-y=-1.5y+20.5y=-18y=-36
There are 14 million kilograms of grain in the three warehouses. The ratio of warehouse A to warehouse B is 3:4, and the ratio of warehouse B to warehouse C is 6:7. How many kilograms of grain are there in each of the three warehouses?
The ratio of a to B is 3:4, that is 9:12
The ratio of B to C is 6:7, that is 12:14
Three cubits: 9:12:14
9x+12x+14x=1400
x=40
Warehouse A: 9 * 40 = 3.6 million kg
B: 12 * 40 = 4.8 million kg
C: 40 * 14 = 5.6 million kg
Solve the equation: the difference between 3 and 2 / 5 minus a number is 2 and 1 / 3, find the number
17/5-x=7/3
x=17/5-7/3
x=51/15-35/15
x=16/15
5 of 8: x = 1 and 1 of 2: (5-2 and 3 of 5) solution ratio
Let Sn be the sum of the first n terms of the equal ratio sequence {an}, and we know that 3s3 = a4-2, 3s2 = a3-2, then the common ratio q = ()
A. 3B. 4C. 5D. 6
∵ SN is the sum of the first n terms of the equal ratio sequence {an}, 3s3 = a4-2, 3s2 = a3-2. By subtracting the two formulas, we can get 3a3 = a4-a3, A4 = 4A3, ∵ common ratio q = 4
Simple operation of minus 199 and 98 / 99 times minus 11
Negative 199 and 99 / 98 times negative 11 = 199 and 99 / 98 times 11 = (200-99 / 1) × 11 = 200 × 11-99 / 1 × 11
=2200-1 / 9 = 2199 and 8 / 9
As shown in the figure, if the median EF of the isosceles ladder ABCD is 5 and the median ad is 4, then the circumference of the isosceles ladder is 4______ ．
The length of median EF of ∵ isosceles trapezoid ABCD is 5, ∵ AB + CD = 2 × 5 = 10. The length of ∵ waist ad is 4, ∵ the circumference of this isosceles trapezoid is ab + CD + AD + BC = 10 + 4 + 4 = 18
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