Examples for 7th grade (seventh) - page 37

  1. Engine pulley
    remenice 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
    hrniec_1 Diameter of the pot 38 cm. The height is 30 cm. How many liters of water can fit in the pot?
  3. Perimeter of circle
    thalet_1 Calculate the circumference of described circle to the triangle with sides 9,12,15 cm.
  4. Passenger car and truck
    2cars 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?
  5. Metal box
    box1 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.
  6. Grandmother's clocks
    kukuckove-hodiny 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.?
  7. Stone
    kamen 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. Rhombus A2p
    kosostvorec Rhombus area is 13 cm2 and its height is 5cm long . Determine a perimeter of this rhombus.
  9. Crown coins
    coins_1 Jana saves two-crown and five-crown coins. She has ten coins in the cashier. How many two crowns and how many five crowns shw have if she saved 29 crowns?
  10. Surface and volume od cuboid
    kvader Content area of the square base of cuboid is Sp = 36 cm2 and its height 80 mm. Determine its surface area and volume.
  11. Water pool
    water 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.
  12. Stock
    frac 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?
  13. Book
    matematika_encyklopedia To number pages of thick book was used 4201 digits. How many pages has this book?
  14. Wheel
    wheel_1 What is the wheel diameter if on the 0.38 km track turns 128 times?
  15. Parachutists
    parasutism 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.
  16. Euros
    fractal_1 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?
  17. QuizQ
    green_triangle_1 An isosceles triangle has two sides of length 7 km and 39 km. How long is a third side?
  18. Tiler
    asdasd On what surface m2 tiler must lay 30 square tiles, each of which has a side 25 cm?
  19. Three workers
    3workers 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?
  20. Cargo
    kon-povoz 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?

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