Answer: 1 monks and 3 monks are regarded as 1 group, and 100 monks can be divided into 100/4=25 (group).
Because each group has 1 monk, there are 1*25=25 monks (people).
So there was the little monk 100-25=75 (person)
Q: It takes three weeks and three days for three people to finish a job. According to this calculation, how long will it take four people to finish the work? (From 1997 Long Island Primary School Mathematics Competition in new york, USA)
A: It takes three weeks and three days for three people to finish a job. If 1 person finishes a job, it will take three times as many days as before: (3*7+3)*3=72 days.
If four people finish a job, it takes a quarter of 72 days: 72/4= 18 (days).
3. Q: A book has 500 pages, numbered 1, 2, 3 ... respectively. How many times does the number 1*** appear? (From the "Primary Mathematics Olympics" exam in the United States)
Answer: 1~99 can be divided into ten groups: 1~9,10/9, 20 ~ 29...90 ~ 99, 10~ 19. So 1 1+9=20 (times) appears.
From 100 to 199, compared with the previous paragraph, there are 1 00 times for "1" in hundreds, but the situation of "1"in units and tens is the same as the previous paragraph. So there is 100+20= 120 (times).
There is no "1" in the 100 in the third segment of 200~299, 300~399 and 400~499, but the situation of "1" in the single digit and the tenth segment is the same as that in the 1~99 segment, with 20 times each. So 20*3=60 (times)
1 will not appear in 500.
To sum up, the total frequency of * * * is 20+ 120+60=200 (times).
4. Q: Dad and son set out from both directions at the same time, with a distance of 10 km. Father walks 6 kilometers per hour and son walks 4 kilometers per hour. Dad brought a puppy. The puppy ran to his son at the speed of 10 km per hour. When he meets his son or father, he immediately turns around until the father and son meet. How many miles did the dog run?
A: The time for the puppy to run is the time for the father and son to walk.
It took father and son to meet: 10/(6+4)= 1 (hours).
So the puppy ran 1 hour, 10 km.
5. Q: When an old man died, he left 17 horses to his three sons, saying that the eldest got half, the second one got a third and the third one got a ninth, and it was forbidden to kill horses. How to divide it?
Answer: If you borrow a horse, you will get 18. The boss got 9 horses, the second got 6 horses, and the third got 2 horses, which added up to 17 horses, and the remaining one was returned.
Because I am so tired of typing, give it to me ~ ~ It's all typed word by word, and I didn't copy and paste it with any network or computer reference materials.