# Grade - examples - page 195

1. Subsets How many 19 element's subsets can be made from the 26 element set?
2. Hectoliters How many hectoliters of water is in garden barrel with 90 cm diameter and a height of 1.3 m, if it is filled to 80% of its capacity?
3. Geometric progression In geometric progression, a1 = 7, q = 5. Find the condition for n to sum first n members is: sn≤217.
4. Cube cut In the ABCDA'B'C'D'cube, it is guided by the edge of the CC' a plane witch dividing the cube into two perpendicular four-sided and triangular prisms, whose volumes are 3:2. Determine in which ratio the edge AB is divided by this plane.
5. Same area There is a given triangle. Construct a square of the same area.
6. Milk At the kindergarten, every child got 1/5 liter of milk in the morning and another 1/8 liter of milk in the afternoon. How many liters were consumed per day for 20 children?
7. Crates 2 One crate will hold 50 oranges. If Bob needs to ship 932 oranges, how many crates will he need?
8. Collect rain water The garden water tank has a cylindrical shape with a diameter of 80 cm and a height of 12 dm. How many liters of water will fit into the tank?
9. Photo frame A square shape photo with a side length of 20 cm is framed by a 4 cm wide bar. Find the external frame size of this photo (the frame is from all sides)
10. Boys to girls The ratio of boys to girls in a party is 3:5 . If 6 more boys arrived and 4 girls left the party, the ratio of boys to girls would be 5:6 . How many are in the party originally?
11. Dinning room How many different combinations can we choose if there are 3 soups, 5 kinds of main dish and 2 desserts in the dining room?
12. Tv screen The size of a tv screen is given by the length of its diagonal. If the dimension of a tv screen is 16 inches by 14 inches, what is the size of the tv screen?
13. Pexeso Drawing paper has dimensions of 60cm and 840mm. Pupils have to divide it into squares so that they can make a pexeso. What dimension must squares have if their side is to be larger than 3cm and less than 10cm?
14. Perimeter of base The circumference of the base of the rotating cylinder is same as its height. What is the diameter and height of this cylinder with volume 1 liter?
15. Two airports Two airports are 2690 km away. From the first airport, the airplane flies at a speed of 600 km/h, from a second airplane at a speed of 780 km/h. When will they meet if they flew at 10:00? How far from the first airport? What overload in g (g-force) has passed the pilot if he accelerated from 0 to 600 km/h in 3 seconds?
17. Diameter of a cylinder The diameter of the cylinder is 42 cm. How many times does the cylinder turn on a 66m long track?
18. Prime factors Write 98 as product of prime factors
19. Red diplomas He numbers of students with honors in 2013 and 2014 are in ratio 40:49. How big is the year-on-year percentage increase?
20. Pupils There are 350 girls in the school, and the other 30% of the total number of pupils are boys. How many pupils does the school have?

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