# Examples for 8th grade - page 23

- Diofant equation

In the set of integers (Z) solve the equation: ? Write result with integer parameter ? (parameter t = ...-2,-1,0,1,2,3... if equation has infinitely many solutions) - Janitor

Janitor tosses 26 cm layer of snow on the school grounds for 90 minutes. How many friends would have to call for help if snow needs to have bowled for 15 minutes. We assume that at the same time bow all the same amount of snow. - 9-gon

Sum of interiol angles of 9-gon is: - 6-gon

Perimeter of regular hexagon is 41. Calculate its circumradius (radius of circumscribed circle). - Pharmacy

At the pharmacy are in one container 20% solution in the second 50% solution of disinfectant. They need to prepare 24 L of 36-percent solution. What amount of solution from each container is needed to mix? - Runner 2

Marian run 12 meters in 8 seconds. How far would Marian run for 70 seconds, if still run at the same pace? - Distance runner

Distance runner already climbed three fifths of the total route. Thus passed 90 km. How many km he have to stop? How long is his route? - Isosceles trapezoid v3

In an isosceles trapezoid ABCD is the size of the angle β = 71° Determine size of angles α, γ and δ. - Chess

How many different ways can initiate a game of chess (first pass)? - Cuboid aquarium

Cuboid 25 times 30 cm. How long is third side if cuboid contains 30 liters of water? - Hockey players

After we cycle five hockey players sit down. What is the probability that the two best scorers of this crew will sit next to each other? - Price reduction

Price of camera is 800 USD on sale its price reduced to 423 USD. Calculate the percentage reduction in the price of the camera. - Balance

The rod are 1.7 m long hanging weights 2 kg and 12 kg on ends. Where are centre of rod (distance from weight 2 kg) to be in balance? - Pumps A and B

Pump A fill the tank for 12 minutes, pump B for 24 minutes. How long will take to fill the tank if he is only three minutes works A and then both pumps A and B? - Backpack

Large backpack cost CZK 1352, little is 35% cheaper. How much we paid for 5 large and 2 small backpacks? - Children

Margaret and Zdena weighs the same and Petra 3 kg more. Together weigh 156 kg. How much does they weigh? - Bundle of candies

In the store has 168 chocolates, caramel candies 224 and 196 hard candies. How many packages we can do and how many of candies will be in each package? - 7 roses

Peter buys 7 roses. When he pay for it left him 4 euro. If he bought 5 roses left him 40 euros. How many euros had Peter before buying? - Children

Less than 20 children is played various games on the yard. They can create a pairs, triso and quartets. How many children were in the yard when Annie came to them? - Do you solve this?

Determine area S of rectangle and length of its sides if its perimeter is 96 cm.

- «
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
- 40
- 41
- 42
- 43
- 44
- 45
- 46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 54
- 55
- 56
- 57
- 58
- 59
- 60
- 61
- 62
- 63
- 64
- 65
- 66
- 67
- 68
- 69
- 70
- 71
- 72
- 73
- 74
- 75
- 76
- 77
- »

Do you have interesting mathematical example that you can't solve it? Enter it and we can try to solve it.