Who has more than one solution to one math problem in primary school! Some of them have a few questi

The railway between the north and south cities is 357 kilometers long, an express train runs from the north city, and at the same time a slow train runs from the south city, the two cars go in opposite directions, after 3 hours of meeting, the express train travels an average of 79 kilometers per hour, and the slow train travels an average of how many kilometers less than the fast train per hour?

Solution 1, [357-(79 3)] 3

40 (km).

That is, the average distance of slow trains is 40 kilometers per hour, and the average number of kilometers per hour of fast trains is 79 kilometers is known, and the average number of kilometers of slow trains per hour is less than that of fast trains.

79-40 = 39 (km).

A: Slow trains travel an average of 39 kilometers less per hour than fast trains.

Solution 2, 79-(357 3-79).

39 (km).

Answer: (Ibid.).

Solution 3: Set the average distance of the slow train to X kilometers per hour.

79×3+3x=357

3x=357-237

3x=120

x=40 (km).

79-40 = 39 (km).

Hello: Here are two questions for reference:

1. Repair a 300-meter-long canal, 2/5 of which was completed in the first 6 days, according to this calculation, how many days will it take to complete this canal? (There are more than 10 ways to solve the problem).

2. Master Wang processes a batch of parts, the number of parts completed on the first day accounts for 30% of the total, if 16 are reprocessed, you can complete 1 2 of this batch of parts, how many parts are there?

1.There are 90 apple trees and pears in the orchard, and the number of apple trees is 4 5 of pear trees. How many pear trees are there?

2.Enclose a cuboid with a 24 cm long iron wire, the ratio of the length to width of the cuboid is 2:3:1, and what is the volume of this cuboid.

An isosceles triangle has a circumference of 18 courtship sides.

The solution is that the circumference of the isosceles is 18 because it is necessary to satisfy 1 side + 1 side 3rd side, 1 side - 1 side 3rd side.

If the length of one waist is x, then the other waist is x, and the third side is 18-2x, then 2x 18-2x 18-2x 0 then x=6 or x=8 because of the even number

3 ten, 3 ten, 4 = 10 (only).

The meaning of the title is: 3 birds staying in the tree and 10 birds flying away + 4 other birds flying away, how many birds are there?

solution, 3+3+4

10 This is a basic arithmetic operation, just add it up.

There were already 6 of them, but three of them were going to go, and four of them were coming, so it should be.

6 3+4=7, you're right.

It should be 3+3+4

10 Thank you for clicking to adopt.

The numerator of this fraction is the least common multiple of 3,7,9 63 and the denominator is 2,4,8 of the greatest common divisor 2

This score is 63 2

1.Your topic originates from the question of [100 Yuan and 100 Chickens] in ancient China. (Zhang Qiujian arithmetic) 100 yuan to buy 100 chickens, chickens 3 yuan, chicken mothers 2 yuan, chicken chicks 1 yuan 3. Ask how many you bought.

There are several answers to your question. Of course, if you remove the case of buying [0] of a certain fruit, it is estimated that there are at least 4 cases.

Let's convert the number of watermelons and apples into the number of plums.

An apple is equal to the money of 10 plums, and a watermelon is equal to the money of 50 plums. You can refer to it below.

In fact, column equations are a knowledge that students from the sixth grade and above should be proficient in or gradually exposed to. It's good to drill hard. Of course, it is also appropriate to throw it away now and not think about it. I think.

1.Let's say you buy 1 watermelon.

If you buy x plums, then 99-x apples.

5 + solution gives x = 60

In this question, only when you buy 1 watermelon, x is an integer).

2.(1) = 7/13 * (20 + 20-1) = 7/13 * 40-7

273/13

21 (2) = 4/17 * (40-6).

136/17

There are x people in the group.

x*3/4+3/4=x

The solution is x=34

1 watermelon, 39 apples, 60 plums.

Adding two zeros equals an expansion of 100 times, and adding the original number is 101 times, so 4545 101 45

So the original number is 45

The original number is expanded by 100 times minus the original number, which is 99 times the original number. So 4455 99 is also 45, so the original number is 45

Scheme 1: (100+1)xx=4545

x=4545÷101

x=45 Scheme 2: (100-1)xx=4455

x=4455÷99

x=45 Scheme 3: (4545-4455) [100+1-(100-1)]=90 2=45

Let this number be 10x+y

1000x+100y + 10x+y=45451000x+100y - 10x+y)=4455 The solution is x=4 y=5

So it turned out to be 45

The original number was 45

Solution: Let the original number be x

Equations can be listed according to the meaning of the question.

100x+x=4545

Solution x=45

A: It turns out that the number is 45

The original number is x

And: 100x+x=4545

x=45A: It turns out that this number is 45

I wish you progress in your studies and be happy every day

Let the original number be x, and the new number is 100x, 101x=4545, 99x=4455Subtract the two formulas to give x=45Absolutely!!

Let the original number be x

Adding two zeros is a 100-fold expansion.

100x+x=4545

x = 45, the original number is 45

Let the original number be x, then the sum is 100x plus x is 101x, and the difference is 100x-x is 99x.

101x-99x is equal to 4545-4455, and x is 45

Let the number x 100x plus x equals 4545 solution.