layout

吉林大学远程教育学院

    >>>>   Unit One
    >>>>   Unit Two
    >>>>   Unit Three
    >>>>   Unit Four
    >>>>   Unit Five
    >>>>   Unit Six
    >>>>   Unit Seven
    >>>>   Unit Eight
    >>>>   Unit Nine
    >>>>   Unit Ten
    >>>>   Unit Eleven
    >>>>   Unit Twelve
    >>>>   Unit Thirteen
    >>>>   Unit Fourteen
    >>>>   Unit Fifteen
    >>>>   Unit Sixteen
    >>>>   Unit Seventeen
    >>>>   Unit Eighteen
    >>>>   Unit Nineteen
    >>>>   Unit Twenty
    >>>>   Unit Twenty-one
    >>>>   Unit Twenty-two
    >>>>   Unit Twenty-three
    >>>>   Unit Twenty-four
    >>>>   Unit Twenty-five
    >>>>   Unit Twenty-six
    >>>>   Unit Twenty-seven
    >>>>   Unit Twenty-eight
    >>>>   Unit Twenty-nine
    >>>>   Unit Thirty

Background Information | Synopsis | Warm-up activity | Text |

Warm-up activity

1. What puzzled Mr. Johnson?

He was puzzled by the fact that most of the trains he saw at the crossing at night traveled eastward.

2. Why did Mr. Johnson want to solve the puzzle?

Because he was curious about it.

3. Why did Mr. Johnson go to the railroad crossing watching the train pass?

He suffered from insomnia and after watching the train pass, he would have a good chance of falling asleep.

4. Who helped Mr. Johnson find out the solution?

The local doctor, who was also an amateur mathematician.

5. How did the doctor explain to Mr. Johnson?

The doctor used the mathematics: probability , reasoning the time when the train passed to explain to him.