题干

某日王老师佩戴运动手环进行快走锻炼,两次锻炼后数据如表.与第一次锻炼相比,王老师第二次锻炼步数增长的百分率是其平均步长减少的百分率的3倍.设王老师第二次锻炼时平均步长减少的百分率为x(0<x<0.5).

项目

第一次锻炼

第二次锻炼

步数(步)

10000

①

平均步长(米/步)

0.6

②

距离(米)

6000

7020

注:步数×平均步长=距离.

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    Several days ago, Brenda had a car accident that led to one of her legs being cut off. Since then she didn't talk to anyone.

     “I wish I could bring her friends to visit her,” said Brenda's mother. “But it's a long bus trip.” The nurse smiled, “Don't worry. We have a plan.”

    Later that day, the nurse had taken Brenda to another room. “Here's your new roommate, Annie Wiggle-Do,” the nurse introduced a dark-hair teenager on the other bed.

    As soon as the nurse left, she jumped out of her bed with her only foot and sat at the other end of Brenda's bed, “I lost my leg from bone cancer,” she said. “What happened to yours?” Brenda was so shocked that she couldn't say a word. “You're lucky.” Annie continued. “You've still got your knee. They had to take mine.”

     “I'd like to have a chat with you, but my friends are coming any time now, so I have to get ready.” Annie said when she took off her hair! Her head was completely bald(秃头的).

     “Oh, I forgot to tell you, the medicine they gave me to kill the cancer also killed my hair.” Annie looked out her wigs(假发), brown and yellow, short and long, straight and curly.

     “That's why I thought up ‘Annie Wiggle-Do'.” Annie smiled. “Get it? Any wig will do? Annie Wiggle-Do?” “When Annie's friends came, she introduced Brenda to them all. Before long, Brenda started chatting with Annie and her friends. They didn't make her feel like a strange person at all!

    The girls shared their names with each other. When it was time to go to bed, Brenda said, “Good night, Annie-Wiggle-Do. Can't wait till morning.”