Percentage application questions for 6th grade equation solutions plus answers

There are 120 boys in the sixth grade of a school, of which the number of girls is boys, and it is known that the number of sixth grade students accounts for 25% of the whole school, how many students are there in this school?

Answer: Equation: Solution: Let the number of students in the whole school be x.

x×25%=120+120×

Equation: (120+120 or 120 (1+.)

Hehe, I happened to be in the sixth grade, I hope I can.

Given that the number of students in school A is 40 percent of that of school B, the number of girls in school A is 30 percent of the number of boys in school A, and the number of boys in school B is 42 percent of the total number of students in school B, what percentage of the number of girls in the two schools is the total number of students in the two schools?

Answer If the number of students in school B is 1, the number of students in school A is 1*40%=, and the ratio of girls to boys in school A is 3:10, that is, the number of girls in school A is 3 13 of the number of students in school A, that is. Number of girls in School B:

1-42%)*1=, the number of female students in the two schools is 12 130 + 58 100, the total number of students in the two schools is 1+, and the proportion of female students in the total number is: (12 130 + 58 100) (1+

It should be like this

There are 20 boys in my class, and the number of boys is 10% more than the number of girls.

Solution: There are x number of female students.

x+10％x=20

..Sixth grade, too far away from me...

Grade 6 Math Percentage Problem Solving Skills: The key to percentage problem problems is to find the unit "1", determine whether the unit "1" is known or unknown, use multiplication to calculate the known, divide the unknown, and find the relative percentage.

The question types are: 1. Find out what is the percentage of a number, multiply the corresponding fraction by a number, such as find what is 50 of 250, that is, 250 50.

2. If you know what percentage of a number is, find this number, if you know that 25 of a number is 50, find this number, you need 50 25.

Find how many percent more or less than a number, find what the number is, such as more (or less) than 20 20, find what the number is, multiply 20 (1+20) or 20 (1-20).

The skill of solving the 6th grade percentage application problem is to find the equivalent relationship, solve the result, and then turn it into a percentage.

Find the unit one, then divide it by the unit one to calculate how many percent the reduction is the whole. That is, divide the difference by the unit one.

Brief introduction. The requirement to be able to answer fraction and percentage application questions generally refers to being able to understand the meaning of the application questions, master the most basic quantitative relationships, correctly distinguish the calculation methods, be able to calculate in columns, and be good at testing the rationality and accuracy of the answers.

Due to the quantitative relationship between fractions and percentages, compared with integer problems, there are both commonalities and particularities, which requires students to understand both their commonalities and their particularities, so that students' cognitive level can be improved.

In the two piles of coal A and B, the original quality of the coal in the first pile is 5 8 of the coal in the second pile, if 22 tons of coal are transported from the B pile of coal to the first pile, then the quality of the coal in the first pile is 7 9 of the B pile, how many tons of coal are in the original A and B piles?

Idea: Let the sum of the masses of the two piles of coal A and B be the unit "1", (the sum of the masses of the two piles of coal A and B is an invariant).

The key is to find out the corresponding fraction of 22 tons of coal.

First, find the share of the sum of the mass of the two piles of coal in the original pile of coal, and then find the share of the sum of the mass of the two piles of coal after the coal of pile B is transported to pile A for 22 tons. Finally, the mass of the two piles of coal A and B is found. This is shown in Figure 1 below

Solution: It turns out that the share of the sum of the mass of the two piles of coal is: 5 (5 10) 5 13;

After B transports 22 tons to pile A, A's share of the sum of the mass of the two piles of coal A and B is:

7 (7 10) 7 16;

The corresponding fraction of 22 tons of coal is: (7 16 - 5 13), and the sum of the masses of the two piles of coal A and B is:

22 (7 16-5 13).

22x208/11

416 (tons);

The original mass of the coal pile was: 416x5 13 160 (tons);

The original mass of the coal in the B pile was: 416-160 256 (tons).

Answer: The original mass of pile A was 160 tons, and the original mass of coal pile B was 256 tons.

Solution: Let the sum of the masses of the two piles of coal A and B be, and the original quality of the coal pile A can be obtained according to the title:

5 (5 ten 8) 5 13, when transporting 22 tons of coal from pile B to pile of coal, the quality of coal pile A is: 7 (7 ten 9) 7 16, according to the meaning of the title:

7 16 a 5 13 22

22 (7 16-5 13).

22x208/11

The original quality of the coal was:

416x5 13 32x5 160 (t).

The original quality of the coal in the second pile is:

416-160 256 (tons).

Answer: The original mass of pile A was 160 tons, and the original mass of coal pile B was 256 tons.

27. To put the concentration as:

4% kilogram of pesticides, diluted to the concentration of the solution, how many kilograms of water need to be added?

It is necessary to add a kilogram of water.

a=a=kilograms.

Add kilograms of water. 28. A worker rides a bicycle from home to the factory at the same time every morning, and if he travels at a speed of 16 kilometers per hour, he can arrive at the factory 15 minutes before the factory work time; If you are traveling at a speed of kilometers per hour, then on the factory.

Arrive at the factory 15 minutes after the shift. (1)

Ask for the distance from the worker's house to the factory.

2) How many hours before the factory start time can this worker get from home at a speed of 16 kilometers per hour every morning and arrive at the factory 15 minutes before work?

1) Set the scheduled time to a hour.

16（a-15/60）=

16a-4=

a = 1 hour.

Distance = 16 (1-1 4) = 12 km.

2) 1 hour before work.

29. A store has a batch of cotton cloth.

Sell 2 9 a day

The next day sell the remaining 2 7

The third day makes up the remaining 1 3 on the second day

At this time, the store has 780 meters of cloth, and asked how many meters of cloth was originally stored?

Solution: Let it be that there is a step a meter.

On the first day, 2 9a meters were sold, and 7 9a meters remained.

The next day 7 9a 2 7 = 2 9a meters were sold, leaving 7 9a (1-2 7) = 5 9a meters.

5/9a×（1+1/3）=780

5/9a=780×3/4

5/9a=585

a = 1053 meters.

It turned out that there were 1053 meters of cloth.

30. A and B set off from the same place and walked in the same direction, A rode a bicycle and B walked. If B goes 12 kilometers first, then A can catch up with B in 1 hour; If B walks for 1 hour first, then A only uses 1 2

hours to catch up with B. Find the speed of two people.

Solution: Let the speed of B be a kilometer hour.

The speed of A is 12 1 + a = a + 12 km/h.

a×1=（12+a-a）×1/2

a = 6 kmh.

The speed of A is 12 + 6 = 18 km/h.

Need hi I'll send you an email.

It is necessary to apply the problem, and it is a percentage problem that can be divided or equations. High bounty, hurry! Hehe, I happened to be in the sixth grade, and I hope to be able to adopt itSixth grade, too far away from me...

1.(2000-1600)/2000

17.The topic is not complete.

18.Ditto.

19.Ditto.

20.No.

21.Not complete.

1.(2000-1600)/2000

17.The topic is not complete.

18.Not complete.

19.Not complete.

44/[(1-60%）/(60%/15%)]21.Not complete.

1.There are 80 bottles of Coke in the store, and the number of bottles of Coke is 1/5 less than that of Sprite, how many bottles are there in Sprite?

Sprite has. 80 (1-1 5)=100 (bottles)2 A train has traveled 808 kilometers from Shanghai to Tianjin, and there is still 1/3 left, how many kilometers is the railway from Shanghai to Tianjin?

The railway length from Shanghai to Tianjin.

808 (1-1 3) = 1212 (km).

3.There is a batch of potato chips in the mall, which sells 2/5 of the total in the morning and 4/8 of the total in the afternoonThere are 54 bags left that are not sold How many bags are there in this batch of potato chips?

This batch of potato chips has:

54 (1-2 5-4 8) = 540 (bag) 5Uncle Zhang's family has 15 peach trees, and the number of pear trees is two-thirds of that of peach trees and two-sevenths of apple trees.

Pear trees have. 15*2 3=10 (trees).

Apple trees have. 10 (2 7) = 35 (trees).

6.There are 400 cows, 1/4 more than sheep, how many sheep are there?

Sheep have. 400 (1+1 4) = 320 (head).

Go to the bookstore and buy an exercise book for a few dollars, and you will have a lot of them.

Do you want the questions and answers from the textbook!!

Hello! "Textbook 1+1" has all the answers.