UCSD MSF R2 已录 附群二维码 TL，BG，面经及我的答案

躲进露露怀里

不出意外的话应该就选择UCSD啦
有2021 full MSF的小伙伴可以dd我呀，人多的话我们拉个群

2.19更新：
BG:中外合作专业2+2，国内GPA2.83 国外3.89
GRE326 免语言 三段实习

TL：
12.13提交申请
1.22收到面试邀请
1.29面试
2.12收到预录取
2.24收到录取
面试题（从论坛里扒的，但是我找不到原帖了，抱歉抱歉）：
1.数到 1 Million 要用的时间？
2.25kg 的大米有多少米粒？
3.全世界海洋里有多少条鱼？全世界海洋里一共有多少条鱼？怎么计算的？还需要什么信息才能得到更准确的答案？
4.How many people worldwide are in automobiles at any given time?
5.此时此刻有多少 automobile 在公路上跑？
6.Tell me how you would determine the number of times you could say the English alphabet in 24 hours. In doing so, please share all your assumptions with us so we can understand how you are figuring out this problem. What pieces of information do you need to find the real answer to this problem?
7.How much money is spent in total on shoes by everyone living in your country? How much of that is spent on sandals? 还让说出如果要得出准确数所需要的 information?
8.How many taxi cabs are there in the largest city in your home country? How many are currently being driven and how many are not? 也是提出 assumption, 但没说需要 3 个 information,只说 what pieces of information would you need to know to come up with a more accurate answer?
9.一只圆珠笔能写多远？What distance will a ballpoint pen write? How did you come up with this answer and what assumptions are you making? What three pieces of information would you like to have in order to provide a more accurate answer?
10.人一辈子要睡多长时间的觉？
11.How many pieces of popcorn does it need to be filled in the cinema? 有多少 unpoped 的？
12.If you played your favorite song continuously for a year, how many times would it play? How did you come to this number and what assumptions are you making? What pieces of information would 13.you need to know to come up with a more accurate answer?
14.How you would determine how many loaves of bread are consumed in a single day around the world? How did you come to this number and what assumptions are you making? What pieces of information would you need to know to come up with a more accurate answer?
15.假设从地球走路走到月球是可行的，需要几年时间？给出 assumption，以及什么 info 可以让结果 more accurate.
Estimate the number of 10 years old children in your state.


自己写的答案：
1. First, we need to know how many digits there are from one to one million. There're 9 one-digit numbers, 90 two-digit numbers, 900 three-digit numbers, 9000 four-digit numbers, 90000 five-digit numbers, and 900000 six-digit numbers. So they're totally about 6 million digits. I can say three digits in a second so totally I need 2 million seconds.

2. First of all, I can weigh a thousand grains of rice. For example, we can assume that a thousand grains of rice are 20 grams. So there would be 25*1000/20*1000= 2million and 500 thousand rice.

3. Because of the flow of the ocean, we can divide the world's oceans into several parts and calculate them separately. First, we need to capture about 1000000 fish, big or small, and tag them. In a few months, we need to catch another 1000000 fish. Look at how many of these fish have our markers. We can estimate the total number of fish in the sea by the proportion of the 1000000 fish with our mark. Because I think there are more than 100 billion fish in the sea, so I chose to catch at least one million fish. In fact, there is a lot of fish in the deep sea that we can't catch, and we know very little about the deep sea. This will have a big impact on our estimates. If we try to catch some fish at different depths, our results may be more accurate

4. When I was an undergraduate, I read that every nine people in the world have a car on average. So there are about 800 million cars in the world. For me, I was driving for about 14 hours last week. That's one-twelfth of a week. Due to the existence of buses, I estimate that there will be three people on average on each bus. So at this moment. There should be 800000000 / 12 * 3 = 200000000 people in the car. If there is a more accurate average number of people in a car or how many cars are on the road at this moment, the answer will be more accurate.

5.  When I was an undergraduate, I read that every nine people in the world have a car on average. So there are about 800 million cars in the world. For me, I was driving for about 14 hours last week. That's one-twelfth of a week. So they're about 800000000/12 = 66 million cars on the road now.

6.

7. First of all, I believe in GDP data, I can easily know how many shoes China will sell in 2020. So the big question is how many sandals are in these shoes. It's very cold in northern China, so I don't think people need to buy sandals. About 700 million people in the South use sandals, half of the 1.4 billion people. For me, I may only buy 5-6 pairs of shoes a year, and only 1-2 pairs of them will be sandals. So about a quarter of them are sandals. So we can divide the total price of shoes sold by 2 and then divide by 4 to get the answer.

8.

9. Fortunately, Xiaomi, a very famous brand in our country, released a pen in 2019. In their advertisement, they claimed that the pen could write 1600 meters, four times as much as an ordinary pen. So I think an ordinary pen can write about 400 meters. If I haven't seen this ad. I need to measure how high the ink is in the refill first. Then use this pen to draw a straight line about 5 meters to measure how much ink is consumed. So I can know how far a pen can write.

10. People sleep 7-9 hours a day on average. It's about a third of the day. The average life expectancy of the Chinese is about 77 years. So people would spend about 77 / 3 = 25.6 years sleeping.

11. We need to know how much popcorn Americans consume in a year and how many movie theaters there are. According to the data I know, Americans can consume 17 billion quarts of popcorn a year. In 2020, there are nearly 40,000 theaters in the country. Then we can calculate that 17 billion divided by 40,000 equals 425,000. 425,000 divided by 365 equals 1,200 quarts. Popcorn off

12. A song takes about four minutes. There're 365*24*60=525600 minutes in a year. So this song will be played 131400 times.

13. I only have bread in the morning, about half a pound. And people eat about four pounds of food a day. So about one-eighth of a day's food is bread. Considering that many parts of the world may not have the habit of eating bread. I think only about a quarter of the people in the world will eat bread, that is, about 1.8 billion people. Then we need to know the amount of food that humans consume every day. Then divide it by four and then divide it by eight to get the answer. In fact, I believe the FAO（Food and Agriculture Organization of the United Nations） will have more accurate data on the daily bread consumption of human beings.

14. It's about 400000 kilometers from the earth to the moon. People walk at about 1.5 meters per second, which is about 5.5 kilometers per second. It takes about 73000 hours to walk 400000 kilometers. That is to say, we need to walk for more than 73000/24/365=8 years without eating or drinking。

15. Tennessee has about six and a half million people. I did some homework about life insurance when I was an undergraduate. So I understand that 10-year-old people make up about 1.5% of the total population. So Tennessee has about 6500000*1.5% = 97500 ten-year-old kids[/free]

史蒂芬黃

求入群～ wechat: snoopy9512
謝謝

moonstarx

或许可以求tl和bg嘛？感谢w

Doughnutt

同求tl，感谢楼主~

躲进露露怀里

moonstarx 发表于 2021-2-19 11:24
或许可以求tl和bg嘛？感谢w

已经更新啦

躲进露露怀里

Doughnutt 发表于 2021-2-19 23:05
同求tl，感谢楼主~

已经更新啦

CD24

国内2.83？

躲进露露怀里

CD24 发表于 2021-2-20 11:59
国内2.83？

嗯，不高，主要是我中外两个本科学位，算是美本比较加分

meatmeetu

求群

躲进露露怀里

meatmeetu 发表于 2021-2-21 21:40
求群

留一下微信号吧，我加你