5 Olympiad questions write the process How many Olympiad questions Don t write the questions you a

You all know that it's not easy to type so many words, and you can also reward points with a lot of points.

Because 5m + 7n = 129, 5(m + n) <129, m+n < 26

The range of what can happen

5m + 7n = 5 (m + n) + 2n = 129 Therefore, the mantissa of 2n is 4 and n may be 2,7,175m + 7n = 129

5m = 129 - 7n

Since m is a prime number, the mantissa of 7n cannot be 9

n = 25m = 129 - 7x2 = 115m = 23

m+n = 25

15 = 3 x 5

9a8a, the mantissa is a

Because it is divisible by 5, a = 0 or 5

Because it is divisible by 3, 9 + 8 + 2a is a multiple of 3.

a = 09 + 8 + 2a = 17 (non-triplet) a = 59 + 8 + 2a = 27

Therefore, a = 5

168 = 8 x 3 x 7

Therefore, the characteristics of the approximate number are:

a.The sum of the digits is a multiple of 3.

b.The last three digits are multiples of 8.

c.The number before the last three digits - the last three digits = a multiple of 7.

Those who meet the conditions 768768

Suppose that when Li met Zhang, he was x kilometers away from Wang.

Li and Wang want to go in the same direction, x (10 + 5) =x = kilometers.

Wang and Zhang are kilometers apart, so they have already set off (6 - 5) = (hours).

hours, distance from ground A x 6 = 45 km.

Lee's full journey time, +45 10 = 12 (hours) Assuming the tram speed v km/h and the interval time is t hours, then the distance between the two trains is tv km.

v + = tv

v * 12/60) = tv + x (12/60)> = +

v = 18

18t = => t =

Trams travel at 8 km/h and take 9 minutes at intervals.

1.Among the natural numbers from 1 to 500, there are 256 without the numbers 0 and 1.

Analysis: 8 in 1-10, 8 8 = 64 in 1-100, 64 4 = 256 in 1-500.

2.The remainder of this number divided by 12 is 5

Analysis: 17 3 = 5 ......2 17÷4=4……1 17÷12=1……5

4.If x kg of potion with a concentration of 45 is used, then (400-x) kg of potion with a concentration of 5 is used.

According to the question: 45% x + 5% (400-x) = 30% 400

Solution: x=250, 400-x=150

Answer: Use 250 kg of potion with a concentration of 45 and 150 kg of a potion with a concentration of 5.

5.The set price is $x.

According to the question: 85% 8x-8(x-45)=12 (45-35).

Solution: x=200

Answer: The price is 200 yuan, 3, make a mark first, 2, 1, 336

With 25,1,There are 95 without the numbers 0 and 1,1,Several Olympiad questions Don't write the questions that you are not sure about Kneel and beg for the process to be correct.

1.How many natural numbers from 1-500 do not include the numbers 0 and 1?

2.If there is a number of auspicious gestures, divide by 3 remainder 2, divide by 4 remainder 1, then what is the remainder of this number divided by 12?

3.In the following multiplication equation, prqs represents different numbers, so what is p+q+r+s equal to?

pq rqs s s

4.In order to control insect pests, the Institute of Agricultural Sciences prepared 400 kilograms of 30% concentration of two kinds of potions with a concentration of 45% and 5%, how many kilograms should be taken from each of the two medicines?

5.A store** a kind of eye protection lamp, if sold according to the price, each can get a profit of 45 yuan, and now according to the price of the 8 can get a profit, and according to the price of each 35 yuan ** 12 can get the same profit, how many yuan is each price of this commodity?

Set Wang Xiao scored X points in the singing competition.

x=(11*85+x)/12+

12x=935+x+

11x=x=Wang Xiao scored points in the singing competition.

Let's give her a score of x

According to the meaning of the question, the average score of 12 people is (85 11+x), and 12 has an equation.

85×11+x）÷12+

The solution is x=

There are two hypotheses, 1). The average score of 11 does not include Wang Xiao's score, then Wang Xiao's score is x, and there is x=

2）。The average score of 11 includes Wang Xiao's results, which seems to be incomprehensible, and the master confirms it? Hehe.

Solution: Set Wang Xiao scored x points in the singing competition

Correct explanation, but not clearly.

4+7=11 Treat all the numbers that follow as a group, and the sum is 11, with the goal 447, 11=40....7 means that 40 sets of "4 and 7" plus a number 7 are needed

So the fifth digit is exactly 7, then start with him and count backwards, 40 groups, which is 80 digits, so 80 + 1 ("this bit") + 4 ("these four digits") = 85, so it is 5 to 85 digits.

From the circular decimals, it can be seen that the fifth digit and then are all 747474... Appear. 447/11=40。。。7.It can be seen that at least the fifth to the 85th place after the small tree.

Adding oneself is twice as oneself.

Self minus yourself = 0

Self divided by self = 1

So 2 times yourself + multiply yourself + 1 = 81

Obviously 8 2 + 8 8 + 1 = 81

So this number is 8

1.The distance traveled by the bicycle = the distance of the front wheel row = the distance of the rear wheel row The distance of the front wheel row = the circumference of the front wheel The number of laps of the front wheel.

Distance of the rear wheel row = Circumference of the rear wheel Number of turns of the rear wheel.

Number of laps in front - number of laps in rear = 99

Transform the form to find the answer.

Solution: There are x students, each of whom has bought Y books. 3x horizontal line books, x field character books, and 5x exercise books were issued. According to the title, it can be obtained:

y -3x = 24, the total number of Tian character books and exercise books left is: 2y - x - 5x ) = 48 books.

Solution: Let the reverse water velocity be x kilometers per hour, and the distance from A to B is y, then take 2 more (y-x) = 6, and the total time is y x + y (x+8) = 2

Lianlid: distance y=12

Hope it helps!