# Grade - examples - page 83

1. Direct route
From two different places A and B connected by a direct route, Adam (from city A) and Bohus (from city B) started at a constant speed. As Adam continued to go from A to B, Bohus turned around at the time of their meeting and at the same speed he returned t
2. Rings groups
27 pupils attend some group; dance group attends 14 pupils, 21 pupils sporty group and dramatic group 16 pupils. Dance and sporting attend 9 pupils, dance and drama 6 pupil, sporty and dramatic 11 pupils. How many pupils attend all three groups?
3. Jumps
At least how many jumps must do frog to overcome the distance of 7 meters? Jump of frog is 18 cm long.
4. Right triangle - leg
Calculate to the nearest tenth cm length of leg in right-angled triangle with hypotenuse length 9 cm and 7 cm long leg.
5. Divisibility 2
How many divisors has integer number 13?
6. Shot
Shot with a mass 43 g flying at 256 m/s penetrates into the wood to a depth 25 cm. What is the average force of resistance of wood?
7. Harvesters
The first harvester reaps the grain from land for 24 hours, the second harvester for 16 hours. For how many hours will take harvest by two harvesters, but the second harvester started working four hours later than the first?
8. Center of gravity
In the isosceles triangle ABC is the ratio of the lengths of AB and the height to AB 10:12. The arm has a length of 26 cm. If the center of gravity T of triangle ABC find area of triangle ABT.
9. Znojmo
From Znojmo to Brno started truck with a trailer at an average speed 53 km per hour. Against him 14 minutes later from Brno started car with an average speed of 1.2-times greater than the truck. How long and how far from Znojmo, they meet if the distanc
10. Product V2
The price of product was increased by 12%. Price increased by 273. How much money it would cost this product, if it was on the contrary by 19% discounted.
11. Fluid
We have vessels containing 7 liters, 5 liters and 2 liters. Largest container is filled with fluid the others empty. Can you only by pouring get 5 liters and two 1 liter of fluid? How many pouring is needed?
12. Weekly service
In the class are 20 pupils. How many opportunities have the teacher if he wants choose two pupils randomly who will weeklies?
13. Equation
Eequation f(x) = 0 has roots x1 = 64, x2 = 100, x3 = 25, x4 = 49. How many roots have equation f(x2) = 0 ?
14. Great Wall of China
Great Wall of China is long 8880 km. Historically valuable however is only 30% of its length. What amount of insurance pays the Peoples Republic of China a month for this monument, if the insurance company charges \$ 10 per year per kilometer of historic s
15. Mukls
The working group, in which 6 workers would ordered job completed within 21 working days. How many workers must be accept yet that the contract will be completed in 14 working days?
16. Speeds
George pass on the way to school distance 200 meters in 165 seconds. What is the average walking speed in m/s and km/h?
17. Students
The class has 22 students. 2 of which has assesement of 2. Count of assesement of 1 is three times more than count of students with assesement of 3. How many students has assesement of 1 and how many students has assesement of 1.
18. Soup
47% of pupils at the school to eat in the canteen, 1/47 of students who eat in the canteen eat lunch soup. a) What percentage of pupils who eat in the canteen and eat soup for lunch? b) What percentage of all pupils of school eat lunch soup?
19. Yogurt
The board is 35 yogurts. How many boards of yogurts must be ordered for 886 people in the canteen?
20. Flowerbed
On the flowerbed was planted 280 flowers - pansies and crayons. During the first week wilts quarter of pansies and an eighth crayons, which is 20% of all flowers. How many pansies were planted on the flowerbed?

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