1. Nickname reading 200 pages of books. If you read 1 1 again, then the book you read is 3/8 of the whole book. How many pages have you been nicknamed to read? If the book must be returned in 8 days, how many pages do I have to read every day in these 8 days?

I have seen it: 200*3/8- 1 1=64.

So what you have read accounts for 64/200=8/25 of the whole book.

Average daily reading: [200-64]/8= 17 pages.

Xiaoming has read a book and has read several pages. If he reads four more pages, the book he reads is 3/ 10 of the whole book. Now he must return the book in eight days, so he must read 1 1 page every day for the remaining eight days. How many pages are there in this book?

I finished it in 8 days: 8* 1 1=88.

If you read four more pages, the rest is: 88-4=84 pages, accounting for1-3/10 = 7/10 of the whole book.

Then the whole book is: 84/[7/ 10]= 120 pages.

3. A class of students went camping. At lunch, according to the calculation of one rice bowl for each person, one vegetable bowl for every two people and one soup bowl for every three people, the whole class received 66 bowls and asked how many students there were in the class.

A person * * * uses:1+1/2+1/3 =11/6.

* * * Student: 66/[1+1/2+1/3] = 36.

4. It took 14 hours to transport a package of goods by car, and it took 1 and 3 times as long to go back, and the speed was 20 kilometers slower than coming back. How many kilometers has the car traveled back and forth?

How many times is one and a third? Suppose it is one and a third times.

Return time: 14/[ 1+4/3]=6 hours.

The time to go is: 6*4/3=8 hours.

In the case of a certain stroke, the speed is inversely proportional to the time. The speed of leaving: the speed of returning = 6: 8 = 3: 4.

So the walking speed is: 20/[4-3] * 3 = 60 km/h.

Return speed: 20/[4-3] * 4 = 80 km/h.

Round trip * * * OK: 60*8*2=960 km.