问题 填空题

在潍坊市“朝阳读书”系列活动中,某学校为活动优秀班级发放购书券到书店购买工具书.已知购买1本甲种书恰好用1张购书券,购买1本乙种或丙种书恰好都用2张购书券.某班用4张购书券购书,如果用完这4张购书券共有______种不同购法(不考虑购书顺序).

答案

解法一:只购买一种书时,购买方案有:甲4本;或乙2本;或丙2本;共三种买法;

购买两种书时,购买方案有:甲2本、乙1本;或甲2本、丙1本或乙1本、丙1本;共三种买法;

因此共有3+3=6种买法.

解法二:设买甲种书x本,乙种书y本,丙种书z本;则有:x+2y+2z=4,即2y=4-x-2z,

①当y=0时,4-x-2z=0,即x=4-2z;因此z的取值有三种:0,1,2;因此共有三种买法;

②当y=1时,x+2z=2,即x=2-2z;因此z的取值有两种:0,1;因此共有两种买法;

③当y=2时,4-x-2z=4,即x+2z=0;因此z的取值只有一种:0;因此共有一种买法.

所以用完4张购书券后,共有3+2+1=6种买法.

选择题
阅读理解

Remembering your dreams will require some efforts on your part. But what your dreams can offer and tell you about yourself will be well worth  it.  Here are some tips to help recall your dreams:

1. Before going to bed, keep a clear mind. Tell yourself that “I will remember my dreams when I wake up”. This is actually a proven and effective way to recall your dreams.

2. Have a regular bedtime and wake-up time. Make this your routine. Going to bed and waking up at a regular time every day could aid in dream recollection.

3. Avoid alcohol consumption and taking medicine before going to bed. These things may prevent you from remembering your dreams.

4. Keep a pencil and a notebook next to your bed so that they will be within reach as soon as you wake up. Having a small lamp by your bedside is also a good idea, so you wake up in the middle of the night and can record your dreams immediately.

5. Do not get out of bed immediately. Upon waking from a dream, lie still in your bed, keeping your eyes closed and moving as little as possible. Let your mind wander among the images of what you have just dreamed.

6. Write down as many details in your dreams as you can, no matter how seemingly unimportant they may be. Do not judge the content or worry if they make sense.

7. Sometimes it may help to draw pictures. A picture is worth a thousand words, as the saying goes. Even if you are not an artist, a simple drawing can help to recall details of your dreams.

小题1:This passage tells you ______ .

A.some useful tips to recall your dreams

B.the way to recall your dreams

C.the reason to remember dreams

D.many details in your dreams小题2: Which of the following ways may NOT be useful for recalling dreams?

A.Avoiding taking alcohol and medicine.

B.Not getting out of bed immediately.

C.Drinking a cup of hot milk.

D.Writing down as many details as possible.小题3:What does the underlined “it” in the first paragraph mean? ______   

A.Remembering your dreams.

B.Some tips to help recall your dreams.

C.Your making efforts to remember your dreams.

D.What your dreams can offer and tell you about yourself.小题4: The author uses the saying “A  picture is worth a thousand words” to_______.

A.show that a picture is better than words

B.say a picture is equal to thousands of words

C.prove that it’s more important to draw pictures than to speak

D.indicate drawing pictures really helps to recall dreams