The equation 2x / 0.3 + 8 / 3 - (1.4-3x) / 0.2 = 0 can't be calculated several times

The equation 2x / 0.3 + 8 / 3 - (1.4-3x) / 0.2 = 0 can't be calculated several times

2x/0.3+8/3-（1.4-3x）/0.2=0
20/3x+8/3-7+15x=0
65/3x-13/3=0
65/3x=13/3
65x=13
x=13÷65
x=1/5

7.8X-X=14.

7.8X-X=14.28
（7.8-1）X=14.28
6.8X=14.28
X=14.28÷6.8
X=2.1

（x-30)(1000-10x)=10000

（x-30)(1000-10x)=10000
（x-30)(100-x)=1000
100x-3000-x square + 30x = 1000
X square - 130x + 4000 = 0
(x-50)(x-80)=0
X = 50 or 80

After a clothing price reduction of 15 yuan, the price is 96 yuan, then the original price of this kind of clothing is 96 yuan______ Yuan

96 (1-15), = 96 (45), = 96 × 54, = 120 (yuan); answer: the original price of this kind of clothing is 120 yuan; so the answer is: 120

（1-1/2006）*（1-1/2005）*（1-1/2004).（1-1/1001）*（1-1/1000）

（1-1/2006）*（1-1/2005）*（1-1/2004).（1-1/1001）*（1-1/1000）
=(2005/2006)*(2004/2005)*(2003/2004)...*(1000/1001)*(999/1000)
=999/2006

A and B start from the same place a at the same time and drive in a straight line in the same direction. Car a can take 240L gasoline at most, and car B can take 200L gasoline at most. You can't refuel on the way, but the two cars can borrow each other's oil. Finally, both cars must return to place a along the same road. Please design a scheme to make one of the cars as far away from the starting point a as possible, and find out the car How many kilometers did you drive? (the fuel consumption of the two vehicles is the same, and each liter of fuel can make one vehicle advance 12 km.)

Suppose that the distance from a to a as far as possible is m km, in which the car lending oil stops after n km, then M = n + (200-x ÷ 12 × 2) × 12 ／ 2 = 1200 km, then oil 1200 ／ 1 is needed 2 = 100 liters, that is to say, 100 liters of fuel is needed for the longest distance (single trip). Then the solution can be obtained as follows: A and B walk 720 kilometers together, B stops to wait for a, and gives a 40 liters of gasoline, a goes back to meet B after another 1200 kilometers, B gives a 40 liters of gasoline, and the two cars return to a at the same time

If a commodity is sold at 80% of the marked price, it will get a profit of 960 yuan. If it is sold at 80% of the marked price, it will lose 832 yuan compared with the cost price. What is the cost price of this commodity?

(960 + 832) △ 1-80% = 1792 △ 20% = 8960 (yuan) 8960-960 = 8000 (yuan) a: the cost price of this commodity is 8000 yuan

The speed of the earth's revolution around the sun is about 1.1x10 to the fifth power km / h, and the sound is very strong

The speed of the earth's revolution around the sun is about 1.1 * 10 to the fifth power km / h, and the propagation speed of sound in the air is about 340m / s, which is larger than that of the earth

If points a and B on the number axis represent - 2,1 respectively, and P is a point on the number axis whose distance to point a or point B is 3, then what is the sum of the distances from all the points P satisfying the conditions to the origin?

If the distance to point a is 3, the point has - 5,1; if the distance to point B is 3, the point has - 2,4. Then the sum of the distances from all the points P satisfying the condition to the origin is 5 + 1 + 2 + 4 = 12

Given that point a and point B (1, - 6) are symmetric about the Y axis, then the coordinates of the symmetric point C of point a about the origin are -

Because point B and point a are symmetrical about the y-axis, and point B is (1, - 6), the coordinates of point a are (- 1, - 6). Because point B is symmetrical with the origin, the symmetric coordinates of point C are (1,6)