There is a passenger carrying 30kg of luggage from the airport by plane, according to the civil aviation regulations, passengers can carry 20kg of luggage free of charge, overweight part per kilogram according to the air ticket grass

There is a passenger carrying 30kg of luggage from the airport by plane, according to the civil aviation regulations, passengers can carry 20kg of luggage free of charge, overweight part per kilogram according to the air ticket grass

Set the ticket price as X Yuan
According to the meaning and known, there are:
(30-20)×1.5%×x=120
15%×x=120
x=120/15%
X = 800 yuan
A: the price of his plane ticket is 800 yuan

The power rule of rational numbers

Multiplicative Association Law: a * b * C = a * (b * c)
Commutative law of multiplication: a * b = b * a
Multiplicative distribution law: a * (B + C) = a * B + A * C

On the horizontal plane, pull the car with the weight of 100N by 50N horizontal pulling force to make the car move 5 meters along the horizontal direction. How much work is done by pulling force and how much work is done by gravity
Please answer the questions as they are on the paper

In the horizontal direction, the object moves forward 5m under the action of 50N tensile force,
According to: w = FS
＝50×5
＝250J
There is no moving distance in the vertical direction, and the work of gravity in the vertical direction is as follows:
W＝Gh,h＝0,G=100N
＝0
A: pull force does 250j work, gravity does 0j work

Let Sn be the sum of the first n terms of the arithmetic sequence {an}, if S3 = 3, S6 = 24, then S12=

Solution
An is equal difference
∴
S3, s6-s3, s9-s6, s12-s9 are also equal
Namely
3,21, s9-24 are also arithmetic sequences
The tolerance is 21-3 = 18
∴(s9-24)-21=18
∴s9=63
∴(s12-s9)-(s9-s6)=18
That is, (s12-63) - (63-24) = 18
∴s12-63=57
∴s12=120

A car travelling in a straight line at a speed of 8 m / s suddenly accelerates at an acceleration of 1 m / s?
There should be a complete process

Initial speed V0 = 8m / s, acceleration a = 1m / s, walking distance s and final speed v
From V ^ 2-v0 ^ 2 = 2As, the final velocity v = root (2As + V0 ^ 2) = 10m / s can be obtained

As shown in the figure, there is a runway with an inner perimeter of 400 meters, known as R = 42 meters, r = 40 meters. If Xiaoming and Xiaogang run a race, each run a lap, Xiaoming runs the inner race, Xiaogang runs the outer race, how many meters should the two start from?

3.14 × (42-40) × 2 = 3.14 × 2 × 2 = 12.56 (m); answer: the starting point of two people should be 12.56 m apart

Given that one root of the equation X2 - (k2-9) x + k2-5k + 6 = 0 is less than 1 and the other root is greater than 2, the value range of real number k is obtained

Let f (x) = X2 - (k2-9) x + k2-5k + 6, then ∵ one root of the equation X2 - (k2-9) x + k2-5k + 6 = 0 is less than 1, the other root is greater than 2, ∵ f (1) < 0 & nbsp; and f (2) < 0, ∵ 12 - (k2-9) + k2-5k + 6 < 0 and 22-2 (k2-9) + k2-5k + 6 < 0, that is, 16-5k < 0 and K2 + 5k-28 > 0, then K ∵ is obtained

On the number axis, points a and B represent rational numbers a and B respectively, and the origin o is just the midpoint of line AB, then the formula 2010a / B + 2010 (a + b)=

-2010. Because AB is symmetric about the origin and opposite to each other, so a + B = 0, a / b = - 1. So it's - 2010

A math problem 1 × 1 / 2 + 2 × 1 / 3 +. + 99 × 1 / 100 =?
How to calculate

Change 1 / 2 to 1-1 / 2, and so on

In view of the phenomenon of waste of water for residents, a city formulates the standard of water consumption for a house of three. The monthly standard water consumption of the house of three is charged for the part exceeding the standard. Assuming that the water charge for the part not exceeding the standard is 1.3 yuan per cubic meter, the water charge for the part exceeding the standard is 2.9 yuan per cubic meter, and the water charge for the house of three in a building is 22 yuan per cubic meter How many cubic meters is the standard water consumption?

Suppose that the standard water consumption of a house of three in this city is x cubic meters. From the Title Meaning: 1.3x + 2.9 (12-x) = 22, the solution is: x = 8. Therefore, the standard water consumption of a house of three in this city is 8 cubic meters