从50张卡片（从1号到50号）中任取一张（每张卡片被取到的可能性相等），取到的卡号为6的倍数的概率是（ ）
|
由题意知本题是一个古典概型，
试验发生包含的事件是从50张卡片中抽1张，共有50种结果，
满足条件的事件是取到的卡号为6的倍数，则包括6，12，18，24，30，36，42，48，共有8种结果，
根据古典概型概率公式得到P=
=8 50
，4 25
故选D．
| 阅读短文，选择正确答案。 |
| One day Tony was crossing the road when he was hit by a car. He fell and broke his arm. An ambulance (救护车) soon arrived and took Tony to a hospital. There a doctor operated on his arm. Then he put the arm in a cast (石膏). Tony couldn't move it at all. "You must keep your arm in a cast for six weeks," the doctor said. "You'll be all right then." At the end of six weeks, Tony went back to the hospital. The doctor took his arm out of the cast. "Can you move your arm, Tony?" he asked. Tony tried to move his arm. At first it was difficult, but soon he could move it easily. "Yes, it's fine," he said. "Thank you very much." "In a few days it will be as good as new," the doctor said. "Just exercises it a little." "Will I be able to play the guitar (吉他)?" Tony asked. The doctor smiled. "Of course you will," he said. "You'll have no problems." "That is good news," Tony said. "Because I couldn't play it at all before." |
| 1. How did Tony break his arm? |
[ ] |
| A. A guitar fell on it. B. A doctor broke it. C. He was hit by a car. D. He fell down the bike |
| 2. How long did Tony have to keep his arm in a cast? |
[ ] |
| A. Several days. B. Less than a month. C. About a month and a half. D. about two months |
| 3. As soon as the doctor took off the cast . |
[ ] |
| A. Tony could move his arm easily B. Tony could move his arm with some trouble C. Tony was no longer able to move his arm D. Tony could move his arm difficultly |
| 4. What did the doctor tell Tony to do after the cast was taken off? |
[ ] |
| A. Exercise his arm. B. Take some medicine C. Come back to the hospital again. D. Play the guitar |
| 5. At last Tony became very happy because . |
[ ] |
| A. he thought he would be able to play the guitar B. the doctor had given him a guitar C. the doctor had told him that he could help him D. The doctor taught him how to play the guitar |