4th Grade Math Supplementary Questions, 4th Grade Mathematics Additional Questions Preferably Detai

When n is an odd number, all the lights cannot be turned off according to the regulations.

Because to turn off a light, it has to go through an odd number of pulls on its switch.

Since n is an odd number, the sum of n odd numbers = odd number, so to turn off all the lights (n), the total number of times you pull the cable switch must be an odd number.

However, because it is stipulated that n-1 switches are pulled each time, and n-1 is an even number, the total number of times the switch is pulled must be an even number.

Odd numbers ≠ even numbers, and when n is an odd number, all the lights cannot be turned off according to the regulations.

When n is an even number, all lights can be turned off according to the regulations. Here's how to turn off the lights:

The lights are numbered 1, 2, 3, 4 ,...,n.Do as follows:

For the first time, the No. 1 light does not move, pull the rest of the switches;

The second time, the No. 2 light does not move, pulling the rest of the switches;

The third time, the No. 3 light does not move, pull the rest of the switches;

For the nth time, the nth light does not move, pull the rest of the switches. At this point all the lights are turned off.

1. The average daily turnover of a small shop is 1306 yuan, please estimate how much is the turnover of this store in November? (4 points).

2. The school organized 270 students to participate in camping activities.

The small triangular tent is limited to 15 people and costs 50 yuan per night; The round tent is limited to 26 people and costs 80 yuan per night.

If you rent only one type of tent, how many will you need and how much will it cost? (3 points) How to save money by renting a tent? Use equations or words to express your thoughts! (3 points).

Yuan. 2:(1).The triangular shape requires 18 tops and costs 900 yuan.

2).The round one needs 11 tops and costs 880 yuan.

3).Rent 10 round tops and 1 triangular shape for 850 yuan.

Because one factor increases by 6, the other factor does not change, and the product increases by 468, so the other factor is 468 6=78 Because one factor does not change, the other factor increases by 6, and the product increases by 144, so the other factor is 144 6=24 If you don't understand, I can explain it to you. One factor increases by 6 and the other factor does not change, and the multiplication rate can be used to get (original factor another factor) + (6 other factor) = original result + 468

Because the original factor is another factor = the original result. So cancel each other out, and we get 6 Another factor = 468

Then the other factor is 78, and the other factor is 24

Put in the parentheses below to make the equation hold.

6947 or 6497

Because all three of them guessed a 6 in the answer, and Xiaoshan only guessed one number correctly, he can be sure that this number is 6, still in the thousands: from 5672 and 4769, it can be seen that the two numbers that Xiaoshan got right the second time were 6 and 7, because the numbers she guessed the third time were all right.

From the question, it can also be concluded that 7 is not in the 10th and 100th places, and 6 is in the 1000th place, so 7 is in the single place, because the second and third guesses are not correct. The remaining 4 and 9 are the hundreds, as long as they are not in his original position.

This number is 6497 or 6947

Because Xiaoshan asked, "Is it 6031?" Xiao Fen said

Guess a number correctly, and the position is also correct. Xiaoshan asked, "Is it 5672?"

Xiaofen said: "I guessed 2 numbers correctly, but the position is not right. Xiao Shan asked

Is it 4769? Xiao Fen said: "Guess 4 numbers correctly, but the position is not correct."

So 6 is in the thousand, 7 is in the single place, and 4 and 9 can be in the hundred and 10 places, respectively.

First of all, these four numbers are;

The first sentence is 6031, and it is correct to guess the position of a number, that is, the first 6 ???

In the second sentence, 5672, guess the position of the two numbers correctly, 6 is one, and the other is 7, then it may be 67??or 6??7

In the third sentence, 4769, guess the position of the four numbers correctly, 7 cannot be the second place, it can only be 6??7, it is 6497 or 6947

According to "Xiaoshan" asked, "Is it 6031?" Xiao Fen said: "I guessed a number correctly, and the position is also correct." "Determined" 6 "in the thousands.

7 "As long as it is not in the tenth place, it can be arranged arbitrarily.

6031 has one right, 5672 has two but the position is wrong, here only 6 is 2 times, that is, the first one is 6, from 4789 can be known to be these 4 numbers, and then according to the previous can be seen that 7 is not in the third place and no longer in the second place, and because the first place is 6, 7 is in the fourth place, that is, 6xx7

This can only push out one of the 6497 and 6947.

4769 is all four numbers right, and none of them are in the right position, so in 5672, the two numbers that are right are 6 and 7, but the position is not right.

Re-analysis of 6031, 6 is right, and the position is also right.

7 It can't be in the ten, hundred, or single place, then it's only a thousand.

There are two combinations of 6xx7, 4 and 9, and the final answer .

Because 4 numbers are , knowing that the first guess was correct is 6, it is 6 on the thousand. The second guess is 7, 7 is not a thousand, not a ten, not a hundred, only a bit. Then there are 4 and 9 indiscriminately, which could be 6497 or 6947

Hehehehehe.

According to the two sentences of the first sentence, 6 is the first number.

Further according to the second and third sentences, it is explained that 7 can only be in the fourth place.

As for 4 and 9, I can't tell.

Both 6497 and 6947 fit the topic.

400 100000000 = 400000000000 (grams) = 400000000 (kilograms) = 40000 (tons).

A: 100 million bunches of these grapes weigh about 40,000 tons.

1: 400g kg.

10: kg*10 4kg.

10000: 10000 10*1000 4 kg*1000 4 tons 100 million: 100 million 100 million * 10,000 4 tons * 10,000 40,000 tons.

100 million strings is 10,000 times that of 10,000 strings, so there are 40,000 tons.

Hello, glad to answer for you!

80 4-15) 2=(320-15) 2=305 2=610 km.

A car travels from A to B for 4 hours, with an average of 80 kilometers per hour, which is more than (median) point of 15 kilometers. How many kilometers are A and B apart?

610 km.

The total score of Chinese, Mathematics and English Science is 89*4=356

Chinese, Mathematics, English: 92*3=276

Science 356-276 = 80 points.

English 2*88-80=96 points.

A drove 40 * 2 = 80 kilometers more than B.

They drove 80 (96-88) = 10 hours.

Because the average score of the four subjects is eighty-nine points, the total score of the four subjects is 89*4=356 points, the average score of the first three subjects is 92 points, the first three scores add up to 92*3=276 points, and the average score of the last two subjects is 88 points, so the scores of the last two subjects add up to 88*2=176 points.

Then the score for science is the total score minus the total score of the first three subjects, which is 356-276 = 80 points, because the score of the last two subjects is 176 points, so the score of English is the total score of the last two subjects minus the score of science is 176-80 = 96 points.

The second question asks what =. = To make it clear, it is purely manual.

89*4-92*3 is the score of science.

A score of 88*2-Science is an English score.

2. Let the time be t, then 96t-88t=80;If t is 5, then 88*5+40 is the ab distance... Note that A must have passed the midpoint, while B did not, and they met on A's side).

English 96 Science 80

Question 2: I don't know what you're going to do.