# Examples for 9th grade

1. Cuboid
Find the cuboid that has the same surface area as the volume.
2. Mom and daughter
Mother is 39 years old. Her daughter is 15 years. For many years will mother be four times older than the daughter?
3. Right trapezoid
The right trapezoid has bases 3.2 cm and 62 mm long. The shorter leg has a length 0.25 dm. Calculate the lengths of the diagonals and the second leg.
4. Dining room
The dining room has 11 tables (six and eight seats). In total there are 78 seats in the dining room. How many are six-and eight-seat tables?
5. Holiday SMS
Kucera and Malek start from the holiday together. They agreed that if they be 100 km apart, will send a SMS. Kucera traveling at 60 km/h., Malek 90 km/h. They started at 14 hours PM. At what time they send a message?
6. Farm2
The farm bred turkeys, geese, hens and chickens. Everything is 400. Turkeys and geese a hen are 150. No hen has more than one chicken, but some hens has no chick. Half of them is also a quarter of the chickens. When the turkey subtracting 15, we get 75. H
7. Iron fence
One field of iron fence consists of 20 iron rods with square cross-section of 1.5 cm side and a long 1 meter. How much weight a field if the density of iron is 7800 kg/m3.
8. Drunk and alcohol
One drunk measured 2.7 ‰ alcohol in the blood, another 1.75 ‰. How many grams of alcohol in the blood they had if they has 6 kg of blood?
9. Hockey match
The hockey match ended with result 3:1. How many different storylines may have the match?
10. Swing
A child weighing 12 kg is sitting on a swing at a distance of 130 cm from the axis of rotation. How far away from the axis of rotation (center) must sit down his mother weighs 57 kg if she wants to be swing in balance?
11. Field with vegetables
Field planted with vegetables has shape of a rectangular isosceles triangle with leg length of 24 m. At the vertices of the triangle are positioned rotating sprinklers with a range of 12 m. How much of the field sprinkler doesn't irrigated?
12. Perimeter and legs
Determine the perimeter of a right triangle if the length of one leg is 75% length of the second leg and its content area is 24 cm2.
13. Tiles
How many square tiles with the content 121 cm2 has to be ordered for the paving of the square room with a side length of 2.75 meters?
14. Chemical parison
The blown parison (with shape of a sphere) have a volume 1.5 liters. What is its surface?
15. The ship
The ship went upstream speed of 20 km/h in relation to water. River flows at speed 10 km/h. After half an hour, he stopped and returned downstream to the starting point. How long it took way back when even if downstream speed of ship is 20 km/h in relatio
16. Flowerbed
Flowerbed has the shape of a truncated pyramid, the bottom edge of the base a = 10 m, the upper base b = 9 m. Deviation angle between edge and the base is alpha = 45°. What volume is needed to make this flowerbed? How many plants can be planted if 1 m2 =
17. High wall
I have a wall 2m high. I need a 15 degree angle (upward) to second wall 4 meters away. How high must the second wall?
18. Square garden
On the plan with a scale of 1:1500 is drawn as a square garden with area 81 cm2. How many meters is long garden fence? Determine the actual acreage gardens.
19. Orchard
Route passes trapezoidal orchard perpendicular to the parallel sides. It is 80 cm wide. The lengths of the bases are in the ratio 5:3 and the length of the longer base to the length of the path is in the ratio 5:6. How many square meters occupies the ro
20. Neighborhood
I have 7 cups: 1 2 3 4 5 6 7. How many opportunities of standings cups are there if 1 and 2 are always neighborhood?

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