# Examples for 7th grade (seventh) - page 67

1. School Headteacher think whether the distribution of pupils in race in groups of 4,5,6,9 or 10. How many pupils must have at least school at possible options?
2. Weightlifter Weightlifter lifted 75% of its weight. Determine how much weight lifted when he weighs 132 kg.
3. King's birthday To celebrate the king's birthday workers fire 1/5 all purchased rockets. To celebrate the Queen's birthday fire 1/6 of the remaining rockets and to celebrate the birthday of king's son remaining 15,000 rockets. How many rockets they purchased?
4. Hexagon area The center of the regular hexagon is 21 cm away from its side. Calculate the hexagon side and its area.
5. Driver I drive at an average speed of 70km/h, I drive 10 thousand km. How long did it take me?
6. Cancer Of the 80 people 50 people ill cancer. What percentage of people isn't ill?
7. Shots Determine the percentage rate of keeper interventions if from 32 shots doesn't caught four shots.
8. Parallelogram Calculate the missing side of a parallelogram, if you know the perimeter o and one side: a) o = 7.2 cm; b = 1.8 cm b) o = 5.4 cm; a = 1.9 cm
9. Coolant The driver of the car cooler filled with a mixture of 3.9 liters and 2.6 liters of water antifreeze coolant. At what rate are this two components of the mixture?
10. Diameter The diameter of a circular plot is 14 dm. Find the circumference and area.
11. Parallelogram perimeter The ABC triangle with sides a = 5cm, b = 3cm, c = 40mm has the center of the sides of the K,L,M. How many cm have the KBLM parallelogram perimeter?
12. Bicycle wheel After driving 157 m bicycle wheel rotates 100 times. What is the radius of the wheel in cm?
13. Rectangle 39 Find the perimeter and area of the rectangular with vertices (-1, 4), (0,4), (0, -1), and (-4, 4)
14. The cellar Mr Novák has a cellar and a cellar window in the chalet has 0.6 meter square window. The window wishes to place an X-shaped grid in a square. He uses iron welded bars. Calculate the lengths of individual bars and what the total length of the bars he has t
15. Percents - easy How many percent is 432 out of 434?
16. Volume and area What is the volume of a cube which has area of 361 cm2?
17. Trapezoidal prism Calculate the surface of the quadrilateral prism ABCDA'B'C'D 'with the trapezoidal base ABCD. The height of the prism is 12 cm; ABCD trapezoidal data: AB base length is 8 cm, CD base length is 3 cm, BC arm length is 4 cm, and AC diagonal length is 7 cm. L
18. Proportion write the following proportion 8 is to 64 as to 2 is to x
19. Seagull Artificially created island in the shape of a circle with a radius of 50 m is overgrown with grass. The only exception is a landing area for helicopters in the shape of a rectangle measuring 15 m and 8 m. What is the probability that the flying seagull (wi
20. Boys and girls There are 28 girls in the hall. 5/7 of all children are boys. How many children and how many boys are there?

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