# Grade - examples - page 87

1. Sportsman
A trained athlete is able to exhale after a deep breath still 500 ml of air. At normal inhalation and exhalation is breathing 500 ml of air. Within one minute, one breath and exhaled 14 times. What part of breathing air per day is one exhalation?
2. Rotating cone
Calculate the volume and the surface area of a rotating cone of base radius r = 2.3 dm and a height h = 46 mm.
3. Metal box
How much metal we need for the production of box with dimensions 5 dm, 30 cm and a height of 1 m? Add 12% of the waste and folds.
4. Two numbers
Find two numbers whose difference and ratio is 2.
5. Heart as pump
Heart pumps out 5.17 liters of blood in 1 minute. How many liters of blood pumped per hour and how much per day?
6. Engine pulley
The engine has a 1460 rev / min (RPM). Disc diameter is 350 mm. What will be the disc peripheral speed in RPM? Pulleys on the engine has diameter 80mm, on a disc has diameter 160mm.
7. Toy Cars
Peter has 29 toy cars, Zdenko has 8 toy cars less. How many toy cars has Zdenko?
8. The pot
Diameter of the pot 38 cm. The height is 30 cm. How many liters of water can fit in the pot?
9. On the farm
The farm took 221 tons of potatoes from 17 hectares. How many tons of potatoes taken from one hectare?
10. Three vectors
The three forces whose amplitudes are in ratio 9:10:17 act in the plane at one point so that they are in balance. Determine the angles of the each two forces.
11. Passenger car and truck
From Kutna Hora left at 11:00 clock a truck at 60 km/h. At 12:30 behind him started passenger car at average speed 80 km/h. At what time and how far from Kutna Hora overtake a passenger car truck?
12. Two pipes
One pipe fill one-fifth volume 20 minutes before by second one. The two pipes together will fill the tank in two hours. How long is will fill tank each pipe separately?
In what quadrant is a -1165° angle?
14. Product
The product of two consecutive odd numbers is 8463. What are this numbers?
15. Perimeter of circle
Calculate the circumference of described circle to the triangle with sides 9,12,15 cm.
16. Mean
if the mean of the set of data 5, 17, 19, 14, 15, 17, 7, 11, 16, 19, 5, 5, 10, 8, 13, 14, 4, 2, 17, 11, x is -91.74, what is the value of x?
17. Big factorial
How many zeros end number 116! ?
18. The farmer
The farmer harvested 840 tons of grain in 2006, which was 44% less than in 2005, and one-fifth more than in 2004. How many tons of grain harvested in years 2005 and 2004?
19. Rhombus A2p
Rhombus area is 13 cm2 and its height is 5cm long . Determine a perimeter of this rhombus.
20. Grandmother's clocks
Grandmother's clock is late every hour by half a minute. Grandmother it by set exactly at 8.00 am. How many hours will show after 24 hours.?

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