Page 304 of the 6th grade Olympiad book, 5 questions, 18 questions

40% of the whole journey was walked on the first day, the remaining 30% was walked on the second day, and 60% * 30% = 18% was walked on the second day

On the third day, I walked 40%*75%=30% and 6 kilometers more.

The whole journey is 50 kilometers.

40% of the first day

The remaining 30 on the second day, i.e., (1 40%) 30% = 18% on the third day 6 km more than the 75 on the first day, i.e., 40% 75% 6 km = 30% + 6 km.

A total of 3 days walked: 40% + 18% + 30% 6 km = 88% 6 km, that is: these 6 km are: 1 88% = 12%.

The whole journey is: 6 12% = 50 (km).

Equation solution: Let the whole journey be n kilometers, and the equation is obtained according to the problem

n 40% n (1 40%) 30% 40% 75% 6=n solution: n=50

On the first day, there is 40 of the whole journey, so there is still 60% of the whole journey, and the second day is the remaining 30, so 30 * 60% = 18% of the whole journey is walked, and then there is 1-40% - 18% = 42% of the whole journey, which is the distance of the third day.

On the third day, I walked 6 kilometers more than the 75 on the first day, and 75 on the first day was 40% * 75% = 30%.

That is. 42% of the whole journey = 30% of the whole journey + 6 km.

6 km = 42% of the whole journey - 30% of the whole journey = 12% of the whole journey = 6 12% = 50 km.

Direct column equations.

Solve x 50

Find the right series of equations, and the questions are so simple.

On the first day, there are 40 of the whole journey, and there is still 60% of the whole journey, and the remaining 30 of the second day is 30 * 60% = 18% of the whole journey, and then there is still 1-40% - 18% = 42% of the whole journey, which is the distance traveled on the third day.

On the third day, I walked 6 kilometers more than the 75 on the first day, and 75 on the first day was 40% * 75% = 30%.

42% of the whole journey = 30% of the whole journey + 6 km.

6 km = 42% of the whole journey - 30% of the whole journey = 12% of the whole journey = 6 12% = 50 km. That's the final answer.

Think of the whole process as unit 1

The first day went 40% i.e., the rest.

The remaining 30% of the second day is equivalent to 30% of the whole journey, that is, 75% of the first day on the third day, more than 6 kilometers, that is, 75% x 40% = 6 kilometers more.

After the next day, there was still a whole thing left.

The rest will be done on the third day. That is, it is equal to the sum of 6 kilometers traveled on the third day, so 6 kilometers is the whole journey.

So the length of the whole journey is 6 kilometers.

Summary. Xiao Ming read a book, read 5 8 of the whole book, there are 36 pages left, that is, the number of pages of the whole book is regarded as the whole 1, that is, the remaining 36 pages are 3 8 of the whole book, 36 3 8 is equal to six 96, which is the number of pages shared by this book.

Xiao Ming read a book, and looked at the whole book, 5 8, there are 36 pages left, and there are many pages in this book.

Hello, I'm glad to answer for you, I'll think about it, I'll reply to you later, don't worry.

Xiao Shou Ming read a book, read the whole book 5 8, there are 36 pages left, that is to say, this line of Qinhui 36 pages is the whole book 3 8, then, the whole book 1 8 is 36 pages divided by three, equal to 12 pages, the whole book 5 8, is multiplied by 12 pages, equal to 60 pages.

Sorry, I miscalculated.

36 (1-5-8) = 36 3 8 = 96

Xiao Ming read a book, read 5 8 of the whole book, there are 36 pages left, that is, Chang Jili regards the number of pages of the whole book as a whole 1, that is, the remaining 36 pages of Zhou Qiao are 3 8 of the whole book, 36 3 8 is equal to six 96, which is the number of pages shared by this book.

36 3 8 = 96, that is, the book has 96 pages.

Summary. There are a total of 48 pages in a book, Xiaohong read 5 6 of the book, Xiaoli read 3 8, how many pages each Xiaohong and Xiaoli read.

The answer is as follows: Xiaohong read 40 pages, Xiaoli read 18 pages The specific calculation process is as follows:

According to the conditions in the question, Xiaohong read the loss of this book 5 6, Xiaoli read the book 3 8, all Luliang belongs to the multiple relationship Oh directly multiply the total number of pages to open the wide

36x5/2

90 (pages) Answer: This book is 90 pages in total.

5 times we only consider the worst-case scenario:

1. Divide into 3 groups first, use the balance to weigh the two groups of 33 each, if balanced, then in the third group, if unbalanced, then in the heavier group.

2. The worst-case scenario is that the heavy ball is in the third group. It is divided into , 3, measured by the same method for the second time, and then divided the group containing the heavy ball into , measured again by the same method, and then divided into

5. The worst case is that the heavy ball is in the third group of 2, and then it will be weighed once.

So weigh at least 5 times, and you will be able to find out the overweight ball, and the key to the problem is to divide it into three groups, and weigh two groups with the same number of balls, which is the best way to weigh it.