Examples for 8th grade - page 45

  1. Principal and interest
    bank_pig Peter put € 270 principal into bank and at the end of the year on account was € 282. To what annual interest rate that Peter had deposited money in the bank?
  2. Sugar
    cukr Sugar factory produced 938.1 tons of sugar in 1 day at 14% sugar content . How many tons of pure beet sugar factory processed in 1 day?
  3. Masons
    Pat_a_Mat 1 mason casts 30.8 meters square in 8 hours. How long casts 4 masons 178 meters square?
  4. Parcel
    2186094 parcel has a rectangular shape of a trapezoid with bases 12 m and 10 m and a height 8 m. On parcel was built object with a footprint an isosceles triangle shape with side 4 m and height three-quarters of a meter. What is the area of unbuild parcel?
  5. Rhombus 2
    koso Calculate the area of rhombus which has a height v=48 mm and shorter diagonal u = 60 mm long.
  6. Stamps and albums
    stamp Michail has in three albums stored 170 stamps. In the first album, there are 14 more than in the second and in the second is by 1/5 less than in the third. How many stamps are in the first album?
  7. Supplementary angles
    acuteangles One of the supplementary angles are three times larger than the other. What size is larger of supplementary angles?
  8. Greenhouse
    foliovnik Garden plastic greenhouse is shaped half cylinder with a diameter of 6 m and base length 20 m. At least how many m2 of plastic is need to its cover?
  9. Tree
    strom How tall is the tree that observed in the visual angle of 52°? If I stand 5 m from the tree and eyes are two meters above the ground.
  10. Pool 2
    bazen_pritok The first supply by the pool fill for five hours and the second fill for six hours, drain should be drained for 15 hours. For how many hours the pool is full, when we open both inlet now and outlet open two hours later?
  11. RT 11
    right_triangle Calculate the area of right tirangle if its perimeter is p = 46 m and one cathethus is 18 m long.
  12. CD disc
    CD_disc A compact disc has a diameter of 11.8 cm. What is the surface area of the disc in square centimeters?
  13. Carpenter
    tesari From wooden block carpenter cut off a small cuboid block with half the edge length. How many percent of wood he cut off?
  14. Racer
    car_championship The first racer run at a speed 12 m/s and is 470 meters before the finish and ahead 22 meters before second competitor. At what speed must run the second racer to catch first racer at the finish line?
  15. Motor physics
    car_motor Car traveling at 97 km/h on the highway. Pulling power of the motor is 6 kN. Determine engine power in kW.
  16. Suit
    oblek The suit cost 218 euros. How much cost the pants if it is 40% cheaper than the jacket.
  17. Task
    cube_1 I have homework. The cube has an edge 11 cm long and I must find wall and body diagonal.
  18. Rhombus and inscribed
    rhombus_2 Rhombus has side a = 72 cm, the radius of the inscribed circle is r = 10 cm. Calculate the length of its two diagonals.
  19. Angles
    rhombus_1 Determine the interior angles of a rhombus with area 240.6 cm2 and perimeter 64 cm.
  20. Motion
    bus_1 From two different locations distant 104 km started against car and bus. The car started at 5:30 with average speed 58 km/h. Bus started at 6:40 with average speed 79 km/h. When they meet? How many kilometers went the bus?

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