1. If the length of "one foot" is 8 cm and the length of the desk is 7 feet, then the length of the desk is 56 cm. If each step is 65 cm, then when you go to school, you can count how many steps you have taken and calculate how far it is from home to school.

2. Height is also a ruler. If the height is 150 cm, hold a big tree and put your hands together. The length of this tree is about 150 cm. Because everyone's arms are flat, the length and height between the fingertips of both hands are similar.

3. If you want to measure the height of the tree, shadows are also helpful. Just measure the length of the shadow of the tree and your own shadow. Because the height of the tree = shadow length × height ÷ graph length.

If you want to know how far the mountain ahead is from you, you can ask the sound to help you measure it. Sound can travel 33 1 meter per second, so you can hear the echo by shouting at the mountain and watching it for a few seconds. Multiply the time to hear the echo by 33 1 and divide it by 2.

5、? "Astronomical Recorder" Coral scientists found that corals record time on themselves: they "carve" an annual ring pattern on the body wall every day and "carve" 365 annual rings a year, no more or less.

So, if you want to know their age, just count the annual rings on their body walls. Scientists also found that 350 million years ago, corals "carved" 400 rings instead of 365. The reason is that the earth's rotation was only 2 1.9 hours a day, not 365 days a year, but 400 days.

1, the correct view is that mathematics not only has truth, but also has extraordinary beauty-a beauty as cold and simple as sculpture, a beauty that does not need our weak nature to perceive, a beauty that is not as ornate as painting and music, and a strict perfection that only the greatest art can have.

-Russell (British philosopher, mathematical logician, the main founder of analysis, the advocate and organizer of the world peace movement. )

2. Being good at "retreating", retreating enough and retreating to the original place without losing its importance is a trick to learn mathematics well.

-Hua

3. Mathematics is a tool especially suitable for dealing with any abstract concept, and its power in this field is infinite. For this reason, a book about emerging physics, as long as it is not a pure experimental description, must be a math book in essence. -Dirac

Mathematics is the key to science and the beauty of the universe.

Kepler (German astronomer and optician)

5. Mathematics has two sides. On the one hand, it is a strict science of Euclid. From this perspective, mathematics is a systematic deductive science. On the other hand, mathematics in the process of creation looks like an experimental inductive science.

-Paulia (mathematician and math educator)

6. The same is true of "difficulty". Facing the cliffs, you can't see a crack in a hundred years, but you can cut it inch by inch and foot by foot with an axe. If you keep accumulating, a leap will come and a breakthrough will follow. -Hua (a world-famous mathematician, the founder and pioneer of China's research in analytic number theory, matrix geometry, canonical group and self-safety function theory. )

7. Think, keep thinking, wait for the dawn, and gradually see the light. If I have contributed to the world, it is not because of anything else, but because of my hard work and persistent thinking. -Newton (British mathematician, astronomer and physicist)