Elementary school students 6th grade math problems to ask for expert solutions!!!

The capacity of the pool is set to be in the unit of "1", and the original water volume in the pool is aIt takes n hours for the drain to drain the pool.

Then within one hour, a water inlet 1 9 b water inlet 1 10 drain pipe drainage 1 n according to the conditions can obtain the following two equations.

a (1 n-1 9) = 3 a (1 n - 1 9-1 10) = 5 to get n = 36 13 a = 3 4

Therefore, the original amount of water in the pool is 1200*3 4=900 (liters).

Answer: A pipe flow rate, 1200 9 = 400 3 B pipe flow rate, 1200 10 = 120

Drainage speed, (400 3*5+120*5-400 3*3) 2= 300+400 3

So 3(300+400 3)-400=900

Let me tell you, first find out their corresponding fraction, that is, 1 3-1 5, and then use 1200 to remove, because the amount of water in 1200 liters of water pipe alone is only 1 3, and the two pipes at the same time to enter and then drain 1 5, indicating that their exhaust efficiency ratio is also 1 3:1 5, so use 1200 times 1 10 divided by (1 3-1 5).

This water pipe prostate is not Nima.

Excuse me, where is the problem?

How to answer no questions

There are 27 teachers, if you buy a single ticket to 27 * 30 = 810 yuan, if you buy a group ticket, you want to: 30 * 30 * because the group buys 30 tickets to get a 20% discount, so buy at least 30 group tickets, this must be known) The above comparison, the teacher ticket is at least 720 yuan.

There are 450 students, 450 divided by 30 is equal to 15, so the student ticket only needs to buy 15 group tickets, 20*30*, in summary, teachers and students total: 7200 + 720 = 7920

Detailed enough, right?

Multiply the number of people by the ticket price and multiply the discount and you're good to go.

7872, if you give three students to the teacher, you can get a 20% discount, which is 720The 447 students are 7152, a total of 7872 yuan, which is 138 yuan less than that

The number of subscribers to the "Study Guide" newspaper is 40% of the number of subscribers, the number of subscribers to the "Elementary School Composition" newspaper is 75% of the number of subscribers, the number of people who subscribe to the "Study Guide" newspaper + the number of people who subscribe to the "Elementary School Composition" newspaper = (the number of people who subscribe to the "Study Guide" newspaper + the number of people who subscribe to both newspapers) + (the number of people who subscribe only to the "Elementary School Composition" newspaper + the number of people who subscribe to both newspapers) = the number of people who subscribe only to the "Study Guide" newspaper + the number of people who subscribe only to the "Elementary School Student Composition" newspaper + 2* The number of people who subscribe to both newspapers.

Number of subscribers = number of subscribers only to the "Study Guide" newspaper + only the number of subscribers to the "Elementary School Student Essay" newspaper + the number of subscribers to both newspapers.

So [(40%+75%)-1]*number of subscribers=30, so all grades=2*[30 (40%+75%-1)].

The number of subscribers to the Study Guide is 2 5 The number of subscribers to the newspaper is the number of subscribers to the Essay for Primary School Students.

Assuming that each person subscribes to only one newspaper, then the sum of the number of subscribers to the two newspapers should be 1 and now it is.

The excess is the number of people who subscribe to both newspapers, and 30 is the number of people who subscribe to the newspaper.

And the number of newspaper subscribers accounts for the whole grade.

So there were 200 people in the whole grade.

Thanks for adopting!

There are x number of students in all grades.

50%*x*2/5+50%*x*75%-50%*x=30

The solution is x=400

30 (2 5+75%-1)=200 200 50%=400 There are 400 students in the whole grade.

30 (50%+2 5-75%) = 200 people.

I'm also in 6th grade, and our teacher told me.

Hello! The four-line thick grade is generally 10 years old.

The score is very high, generally above 95.

There are several types of in-scale excitation possibilities:

Only 2910 970 came up with an answer that was an integer, and the answer was 3.

So my sister scored 97 points and came in 3rd.

Hope it helps.

If it helps you, Wangling socks.

With 2910 loss 10 = 291, this is the product of her rank and score, the high burning basis score is generally 95-100, use 291 to remove these numbers, only 97 results are integers, is 3, the socks sold, she scored 97 points, 3rd.

The fourth grade is generally 10 years old.

The score is very high, generally above 95.

There are several possibilities for the following calendars:

Only 2910 970 came up with the answer of the whole banquet search, and the answer was 3.

So my sister Xiangfeng scored 97 points and ranked third.

Factor 2910.

Got 2910 = 2 * 3 * 5 * 97, because the competition score is very high, it is known that it is 97 points, and my sister is envy.

Fourth grade of primary school.

Get an age of 2 * 5 = 10 years old, ranking 3