1. When the student asked the teacher how old he was, the teacher said, "when I was your age, you were just 3 years old; when you were my age, I was 39 years old." so how old is the teacher? 2. Yaya, Benben and LeLe have 73 pieces of sugar. If Yaya eats 3 pieces, Benben and Yaya have the same amount of sugar. If Benben gives Lele 2 pieces of sugar, Lele's sugar is twice as much as Benben's. how many pieces of sugar do they have? 3. There are two pieces of land with a total area of 80 hectares. Three times of the first piece of land is 10 hectares less than two times of the second piece of land. How many hectares are there in each of the two pieces of land? 4. This year, my grandfather's age is six times that of xiaolingmei. A few years later, my grandfather's age is five times that of xiaolingmei. A few years later, my grandfather's age is four times that of xiaolingmei. Q: how old is my grandfather?

1. When the student asked the teacher how old he was, the teacher said, "when I was your age, you were just 3 years old; when you were my age, I was 39 years old." so how old is the teacher? 2. Yaya, Benben and LeLe have 73 pieces of sugar. If Yaya eats 3 pieces, Benben and Yaya have the same amount of sugar. If Benben gives Lele 2 pieces of sugar, Lele's sugar is twice as much as Benben's. how many pieces of sugar do they have? 3. There are two pieces of land with a total area of 80 hectares. Three times of the first piece of land is 10 hectares less than two times of the second piece of land. How many hectares are there in each of the two pieces of land? 4. This year, my grandfather's age is six times that of xiaolingmei. A few years later, my grandfather's age is five times that of xiaolingmei. A few years later, my grandfather's age is four times that of xiaolingmei. Q: how old is my grandfather?

one
The age difference between teachers and students remains unchanged, which is: (39-3) △ 3 = 12 years old
Teacher: 39-12 = 27 years old
two
Ya Ya is 3 yuan more than Ben Ben
After running to Lele for 2 yuan, Ya Ya is 3 + 2 = 5 yuan more than running
At this time, there are: (73-5) / (1 + 1 + 2) = 17 pieces
original,
Gallop: 17 + 2 = 19 yuan
Yaya: 19 + 3 = 22 yuan
Lele: 73-19-22 = 32 yuan
three
Three times of the two plots, a total of 80 × 3 = 240 hectares
Second block: (240 + 10) / (2 + 3) = 50 ha
First block: 80-50 = 30 ha
four
Draw a line diagram to see
Xiaoling's age this year is a multiple of 3 and 4 at the same time
Xiaoling is 12 years old and his grandfather is 72 years old

The height of a mountain is calculated by sea level, but since our earth is round, there is no sea level. Since there is no sea level, how can we calculate the height of a mountain?

Sea level, as the name suggests, is the surface of the sea. It is used to measure the height, also known as altitude. In China, the sea level of the Yellow Sea is a theoretical position, in fact, it is a physical mark, as the measurement reference point. Not every time we measure from the sea level, because there are tides in the sea, the sea level is also changing, It starts from the base point of the Yellow Sea, and any elevation is the base point relative to the Yellow Sea
If you understand the rules of sea level, your problem will be solved

Write the formula and the result
1. When the student asked the teacher how old he was, the teacher said, "when I was your age, you were just 3 years old; when you were my age, I was 39 years old." so how old is the teacher?
2. Yaya, Benben and LeLe have 73 pieces of sugar. If Yaya eats 3 pieces, Benben and Yaya have the same amount of sugar. If Benben gives Lele 2 pieces of sugar, Lele's sugar is twice as much as Benben's. how many pieces of sugar do they have?
3. There are two pieces of land with a total area of 80 hectares. Three times of the first piece of land is 10 hectares less than two times of the second piece of land. How many hectares are there in each of the two pieces of land?
4. This year, my grandfather's age is six times that of xiaolingmei. A few years later, my grandfather's age is five times that of xiaolingmei. A few years later, my grandfather's age is four times that of xiaolingmei. Q: how old is my grandfather?

1. The age difference between teachers and students is the same, which is: (39-3) △ 3 = 12 years old, teacher: 39-12 = 27 years old. 2. Yaya is 3 yuan more than Benben. After Benben gives Lele 2 yuan, Yaya is 3 + 2 = 5 yuan more than Benben. At this time, Benben has: (73-5) △ 1 + 1 + 2) = 17 yuan. Originally, Benben: 17 + 2 = 19 yuan, Yaya: 19 + 3 = 22 yuan, Lele: 73-19-22 = 32 yuan

Is the earth's equator close to the earth's center or is the north and south poles close to the earth's center
Does the earth want more football or more persimmon? That is to say, is it close to the equator or the north and south poles!

It's like the north and south poles
The average distance from the upper surface of the earth's crust (regardless of the undulating factors such as mountains and rivers on the earth's surface) to the earth's center is 6370 km; the average distance from the lower surface of the earth's crust to the earth's center is 6337 km
Average radius of the earth
6371.004 km
Equatorial radius of the earth
6378.140 km
Polar radius of the earth
6356.755 km

Count the number of triangles with the method of Mathematical Olympiad
What is the formula for calculation

The side lengths of all triangles are: 1,2,3,4
There are 16 with side length of 1
There are seven with two sides
There are three with three sides
There is one with four sides
Total: 16 + 7 + 3 + 1 = 27

What is the center of the earth?
Are the seven states on the earth above the four oceans? Or are the seven states one and filled with water?

The oceans of seven continents that float above the dense mass of the earth's surface fill the gaps between the continents

There are three boxes. Box a contains two 1g weights, Box B contains two 2G weights, and box C contains one 1g weight and one 2G weight. The labels on the outside of each box are wrong. Smart Xiao Ming only takes one weight from one box, weighs it on the balance, and corrects all the labels. Do you know how he does it Did you do it?

Take out a weight from the box marked with a weight of 1G and a weight of 2G in the box. If it is 2G, it can be inferred from the title that the box contains two weights of 2G. If it is Box B, the box marked with weight of 1G must be box C containing a weight of 1g and a weight of 2G, and the box marked with weight of 2G is box a containing two weights of 1G

How far is Shenzhou 6 from the earth's center

The equatorial radius of the earth is about 3963 miles (6378.5 kilometers) from its center to the equator. The flight altitude of Shenzhou 6 is 300 kilometers, which is 6678.5 kilometers. However, when we do physics problems, we will ignore the flight altitude and only calculate the radius of the earth

Please write down your thoughts
Car a and B leave from a and B at the same time. Car a travels 72 kilometers per hour, and car a travels 60 kilometers per hour. The two cars return to B and a respectively. They start from the beginning and meet for the second time after 15 hours. How many kilometers are there between the two places?

Because of the second meeting, a and B took the whole road once, and a and B walked together once, so 15 * [72 + 60]% 3 was 660km away

How many meters is it from the earth to the center of the earth

Because the earth is a rotating ellipsoid with slightly bulging equator and flat poles, the distance from different places to the center of the earth is different. The maximum distance from the equator is 6378 km, and the minimum distance from the two poles is 6357 km, with an average of 6371 km