Examples for 7th grade (seventh) - page 36

1. 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.
2. The pot Diameter of the pot 38 cm. The height is 30 cm. How many liters of water can fit in the pot?
3. 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?
4. Perimeter of circle Calculate the circumference of described circle to the triangle with sides 9,12,15 cm.
5. 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.?
6. Rhombus A2p Rhombus area is 13 cm2 and its height is 5cm long . Determine a perimeter of this rhombus.
7. Stone When Peter threw stone in a box of water he discovered that the water level has risen by 9 cm. The box has a cuboid shape, the bottom has dimensions of 24 cm and 14 cm, height is 50 cm. What volume has a stone?
8. Water pool What water level is in the pool shaped cuboid with bottom dimensions of 25 m and 10 meters, when is 3750hl water in the pool.
9. Wheel What is the wheel diameter if on the 0.38 km track turns 128 times?
10. Stock Enterprise sold 7/12 of their products to foreign markets and 2/5 of the remainder sold at home. How many % of the products is still in stock?
11. Parachutists Parachutists during freefall firstly held in groups of 4, then of 6, then 9, 12 and finally of 18 members. How many parachutists jump at least should be, if at each group must all be involved.
12. Book To number pages of thick book was used 4201 digits. How many pages has this book?
13. QuizQ An isosceles triangle has two sides of length 7 km and 39 km. How long is a third side?
14. Euros Michal, Peter, John and Lenka got together 2,400 euros. They share an amount in ratio 2:6:4:3. How many got each of them?
15. Tiler On what surface m2 tiler must lay 30 square tiles, each of which has a side 25 cm?
16. Cargo Weight of cargo car is 761 kg. Weight of car is 23% of the total weight of car+cargo. What is the weight of the cargo load?
17. Three workers Three workers were rewarded CZK 9200 and the money divided by the work they have done. First worker to get twice than the second, the second three times more than the third. How much money each worker received?
18. Fewer than 500 sheep, There are fewer than 500 sheep, but if they stand in a double, triple, quadruple, five and sixth order, one sheep will remain. But they can stand in the seventh order. How many are sheep?
19. Eva When Eva buys 8 packages of cookies 4 CZK left her. If she wanted to buy 10 packages, she would have to borrow 20 CZK. How much money has Eva in her wallet?
20. Complementary angles Two angles are complementary. If one angle measures 10°, what is the measure of the second angle?

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