A math problem. What's the rate of kilogram and ton? A conical coal pile, which covers an area of 15 square meters, is 1.2 meters high, and weighs 1.6 tons per cubic meter of coal. How many times can it be transported by 800 kg truck?

1 ton = 1000 kg
What is the volume of the coal pile
15 × 1.2 × (1 / 3) = 6m3
Therefore, the weight of coal:
1.6 × 1000 × 6 = 9600 kg
It needs to be transported
9600 △ 800 = 12 times
A: 12 times can be finished

Help me to solve a math problem. Make a formula-
Passengers are waiting for check-in in the waiting room of the station, and the number of passengers queuing up is increasing at a certain speed. When the station opens one check-in gate, it takes half an hour to check in all the passengers waiting for check-in; at the same time, it only takes 10 minutes to open two check-in gates to check in all the passengers. There is a passing train, and all the passengers must check in within 5 minutes, How many check-in gates should this station open at least at the same time?

Suppose the original population of the station is x, the increase of the station population is a, and the check-in speed is y, then we can get x + 30A = 30yx + 10A = 20Y, so we can get y = 2A, so x + 30A = 60A, x = 30a, now we need all passengers check in within 5 minutes, assuming n windows are needed, so we can get x + 5A > = n * 5 * yn > = (x + 5a) / 5Y > = (x + 5a)

The area of a square is 20 square centimeters. What is the area of the largest circle in the middle of the square?

Proof: the analysis needs to prove that the largest circle inside the square is inscribed circle. Counter proof: if it is not inscribed circle, then its diameter is greater than or less than the side length of the square. If it is greater than a, then there must be a circle outside the square with any point of the square as the center

A barrel of oil weighs a quarter of a ton. After half of the oil is used up, the barrel weighs seven fourths of a ton. What is the weight of an empty barrel? What is the weight of the original oil?

Oil weight: (1 / 4-7 / 48) × 2 = 5 / 24 tons
Barrel weight: 1 / 4-5 / 24 = 1 / 24 ton

A mathematical problem should have formula and calculation process
A total of 48 cases of export commodities, each of which is worth 24000 yuan, are required to be levied 8% of Yuet. In order to encourage exports, Yuet is actually levied at a 10% discount. How much is the total amount of Yuet?

Tax payable = 48 * 24000 * 8% * 90% = = 82944

You need to write the formula,
For a fish, the head weighs 9 kg, the weight of the head is equal to half of the body and the tail, and the weight of the body is equal to the weight of the head and the tail. Q: how many grams of the body?

12 kg. Let the body of the fish be x and the tail be y. The meaning of the question is: 9 = x / 2 + y x = 9 + y x = 12, y = 3

Ding Ding's mother is on a business trip for nine days. The sum of the nine days is 72. His mother can return on the ninth day. What's the date when her mother goes home?

72 △ 9 = the 8th, so the middle day of the 9 days (the 5th day) is the 8th
8 + (9-5) = 12
A: the day Mom came home was the 12th

There are two engineering teams a and B. A builds 160 meters of road every day, and B builds 120 meters every day. When a finishes three fourths of the road, B will build another five days to complete the rest of the project. The total length of the road is {} meters. A has built {} days

When a finishes 3 / 4 of the road, there is still 1 / 4 left,
B build 120 meters of road every day, and the engineering team will build the rest for another five days
Project completion: 120 * 5 = 600
That is, 600 is one fourth of the length of the road, so the road is 2400 meters long
2400 * (3 / 4) = 1800 m
1800 / 160 = 11.25 days

A math problem. How to write it
It is known that y = (A-2) x + A & # 178; - 4, y is a positive proportional function of X, and the functional relationship between Y and X is obtained

Y = (A-2) x + A & sup2; - 4, y is a positive proportional function of X
A-2 is not equal to 0
a^2-4=0
a=-2
y=-4x

A math problem,
Let two of the equations 2x ^ 2-mx-4 be X1 and X2, and the sum of the reciprocal of X1 and the reciprocal of X2 is equal to 2. The value of M is ()

x1+x2=m/2
x1*x2=-2
1/x1+1/x2=2
be
(x1+x2)/x1x2=2
(m/2)/(-2)=2
m/2＝-4
m＝-8

A math problem. What's the rate of kilogram and ton? A conical coal pile, which covers an area of 15 square meters, is 1.2 meters high, and weighs 1.6 tons per cubic meter of coal. How many times can it be transported by 800 kg truck?