问题 解答题

有蜘蛛、蜻蜓、蝉三种动物共18只,共有腿118条,翅膀20对(蜘蛛8条腿,蜻蜓6条腿,2对翅膀;蝉6条腿,1对翅膀),三种动物各几只?

答案

(1)假设18只动物全是6条腿的,那么蜘蛛的只数就是:

(118-6×18)÷(8-6),

=10÷2,

=5(只),

则6条腿的虫应有:18-5=13(只).

(2)假设剩下的13只全是蝉,那么蜻蜓的只数就是:

(20-1×13)÷(2-1),

=7÷1,

=7(只).

则蝉的只数就是:13-7=6(只).

答:蜘蛛5只,蜻蜓7只,蝉6只.

单项选择题
阅读理解

阅读理解。从ABCD中选出正确的答案。(每题2分,共40分)

It was a winter morning, just a couple of weeks before Christmas 2005. While most people were warming up their cars, Trevor, my husband, had to get up early to ride his bike four kilometers away from home to work. On arrival, he parked his bike outside the back door as he usually does. After putting in 10 hours of labor, he returned to find his bike gone.

The bike, a black Kona 18 speed, was our only transport. Trevor used it to get to work, putting in 60-hour a week to support his young family. And the bike was also used to get groceries(食品杂货), saving us from having to walk long distances from where we live.

I was so sad that someone would steal our bike that I wrote to the newspaper and told them our story. Shortly after that, several people in our area offered to help. One wonderful stranger even bought a bike, then called my husband to pick it up. Once again my husband had a way to get to and from his job. It really is an honor that a complete stranger would go out of their way for someone they have never met before.

People say that a smile can be passed from one person to another, but acts of kindness from strangers are even more so. This experience has had a spreading effect in our lives because it strengthened our faith in humanity(人性) as a whole. And it has influenced(影响) us to be more mindful(注意的,留神的)of ways we, too, can share with others. No matter how big or how small, an act of kindness shows that someone cares. And the results can be everlasting.

小题1:Why was the bike so important to the couple?

A.They used it for work and daily life.

B.It was their only possession.

C.It was a nice Kona 18 speed.

D.The man's job was bike racing.小题2:What does the underlined phrase mean?

A.go very far to see someone

B.walk out on foot to greet someone

C.help someone with one’s best

D.enjoy the moment with someone小题3:We can infer from the text that ________.

A.the couple worked 60 hours a week

B.people were busy before Christmas

C.the stranger brought over the bike

D.life was hard for the young family小题4:How did people get to know the couple's problem?

A.From a stranger.

B.From a newspaper.

C.From TV news.

D.From radio broadcasts.小题5:What do the couple learn from their experience?

A.Strangers are usually of little help.

B.One should take care of their bike.

C.News reports make people famous.

D.An act of kindness can mean a lot.