Grade 5 Mathematics Olympiad 2 questions Rush !! Use it today!

Primary school math Olympiad problems, please don't use the method of column equation solving, which does not help primary school students.

1.After walking for 8 minutes, my brother turned around and went back, and it took a total of 16 minutes to get home, and it can be considered that my brother let my sister go for 16 minutes first.

65 16 = 1040 meters, that is, when the elder brother went to the stationery box and started walking from home, the younger sister had already walked 1040 meters.

75-65 = 10 meters, which means that for every 1 minute of walking, the elder brother can catch up with the younger sister by 10 meters, then 1040 10 = 104 minutes.

2.The speed of the current is 6 kilometers per hour, and after 6 hours of sailing, the water flows 6 6 = 36 kilometers on its own.

In other words, if you sail in still water for 6 hours, you are still 36 kilometers away from the pier.

Similarly, 6 8 = 48 km, which means that if you sail in still water for 8 hours, it is equivalent to an extra 48 km after reaching another pier.

From a difference of 36 kilometers to an extra 48 kilometers, 36 + 48 = 84 kilometers, 8-6 = 2 hours, it can be said that the ship can be 84 kilometers in 2 hours when the water is still water.

84 2 = 42, it is learned that the ship's still water speed is 42 kilometers per hour.

It can be calculated according to the time of the water: 42 6 + 36 = 288 km.

It can also be calculated according to the reverse water time: 42 8-48 = 288 km.

2.set, the speed of the ship is x kilometers per hour.

Then 6(x+6)=8(x-8)x=

1) X minutes to catch up.

75x=65（16+x）

x=1042) with two piers x km apart.

x/6-6=x/8+6

x=288

1.The total time taken by the brother is x

65x+65*8=75x-75*8x=1122.Set the boat in still water with a velocity of x

x+6）*6=（x-6）*8

x=42 so distance: (42+6)*6=288 or (42-6)*8=288

Minutes in km.

1. Solution: Set x minutes to catch up with your sister. Column equation: 75 8+65 8+65x=75x Solution: x=112 Answer: 112 minutes to catch up with my sister.

2. Solution: The hydrostatic speed of the ship is x kilometers per hour. Column Equations:

6 (x+6)=8 (x-6) solution: x=42 then the distance between the two docks: (42-6) 6=288 (km) Answer:

The two terminals are 288 km apart.

Set the time to x minutes.

65（8+8+x）=75x

x=104 set the speed of the ship xkm h

6（x+6）=8（x-6）

x=42 distance 6 (42+6)=288km

Use your own brain.

Brother 1 min 75m Sister 1 min 65m 8 min 600m 8 min 520m

It took 8 minutes for my brother to get home, and it took 8 minutes to walk to the return point after getting his things. These two 8 minutes, my sister is gone (65*8)*2=1040And then while my sister is still walking, it will take 1040 (75*65)=104 minutes.

There should be no horizontal line in 9xyz.

Let the first digit of the number be x, and the last two digits are a (a is a two-digit number), then the original number = 1000x+a, and 9xyz = 9*(100x+a) 1000x+a=9*(100x+a).

2a=25x, only a=25 x=2, or a=50 x=4 or a=75 x=6, the number of the box is

From the meaning of the question, we can know that 1000x+10y+z=9 (100x+10y+z), 100x=80y=8z, 25x=20y+2z, so x is an even number, z=0 or 5, and then find the values of x, y, and z in groups to get the answer

Answer: Solution: By. xoyz =.9xyz, it can be known:

1000x+10y+z=9 (100x+10y+z), 100x=80y=8z, 25x=20y+2z, so x is even, z=0 or 5, when x=2, z=5, y=z, the number is: 225;

When x=4, z=0, y=5, the number is 450;

When x=6, z=5, y=7, the number is: 675;

When x=8, the requirements are not met

Answer: Drugs are hidden in boxes marked with mysterious numbers The key to this question is to roll out four digits. xoyz

is a multiple of 9, and then finds the values of x, y, z

Solution: By. xoyz =.9xyz, it can be known:

1000x+10y+z=9 (100x+10y+z), 100x=80y=8z, 25x=20y+2z, so x is even, z=0 or 5, when x=2, z=5, y=z, the number is: 225;

When x=4, z=0, y=5, the number is 450;

When x=6, z=5, y=7, the number is: 675;

When x=8, the requirements are not met

A: The drugs were hidden in boxes marked with a mysterious number

There is no horizontal line on 9, otherwise it would not be possible.

Based on xoyz =9xyz

It can be seen that 1000x+10y+z=9 (100x+10y+z) is simplified to 25x=20y+2z=> Since 25x=2 (10y+z) analyzes the above formula, we can see that x is an even number, and 10y+z is an integer multiple of 25 (according to the title, x, y, z cannot all be 0).

Then there are: when x=2, z=5, y=2, the number is 2025;

When x=4, z=0, y=5, the number is 4050;

When x=6, z=5, y=7, the number is 6075;

The answer to this question is .

Solution: Set Qiangqiang to have x milk candy, and Lili has (x+6) milk candy.

x+（x+6）=40

Solution: 2x=34

x=34/2

x=17A: Qiangqiang has 17 toffee.

Solution: Set the width to be x and the length to be 2x.

x+2x=72/2

Solution: 3x=36x=12

Answer: The rectangle is 12 wide and 24 long

It is not easy to type, and the watchtower owner adopts it

1.Set strong and strong with x grains of toffee.

x+x+6=40 x=17

2.Let the width of the rectangle be x cm.

2x+2x×2=72 x=12

So, the length is 2x = 24 cm.

1.Solution: If there are x strong and strong, then Lili has (x+6) x+x+6=40

2x+6=40

2x=34x=17 and then bring x in (x+6) and that's it, 2Solution: If the width is x, the length is 2x

2（x+2x）=72

2x+2x =72

4x=72x=18 and then bring x into 2x.

Strong 17 grains, set strong and strong with x grains Lili x+6

2x+6=40

Set the width of xcm and the length of the setting to 2xcm

x+2x）x2=72

A cent is 5 yuan.

C gets a snack ( 4 + 3 ) 3 = 7 3

That is to say, the price of each pack of dim sum is 7 (7 3) = 3 yuan, so A gives out 4-7 3 = 5 3 packs of dim sum.

5 3 * 3 = 5 yuan.

To be honest, I don't quite understand. The answer should be $4.

Because. Forehead. The sum of the snacks is also 7 packs.

Answer: The time used to go down from top to bottom for 36 levels is 36 1=36, and the time used to go up from bottom to level 60 is 60 5=12, the relationship between time is 3:1, the column formula is 36 3x=60-x, and the solution is x=6, so the escalator has 36 + 18 = 54 steps when it is stationary.

36÷1=36

36＋3x=60-x =6

36+18=54 I didn't use the equation, I saw it clearly, it was a gear shift!!

Have you ever studied equations?

1) Set up a child ticket of x yuan.

x+2x=3x=x=

A: Children's tickets.

2) Set a pair of badminton rackets for x yuan.

x+19=x=38

A: A pair of badminton rackets is 38 yuan.