Examples for 8th grade - page 30

  1. Two diggers
    two-diggers There are two diggers. One digger digs a pit 46 hours second gidding 2 times faster. a) how long took to dig a pit second digger b) how long took dig together
  2. Internal angles
    mo-klm The ABCD is an isosceles trapezoid, which holds: |AB| = 2 |BC| = 2 |CD| = 2 |DA|: On its side BC is a K point such that |BK| = 2 |KC|, on its side CD is the point L such that |CL| = 2 |LD|, and on its side DA the point M is such that | DM | = 2 |MA|. Dete
  3. Bomber
    b52 Bomber flies 10 km at 600 km/h. At what horizontal distance from the target, must pilot drop the bomb to hit the target? Don't care about air resistance and consider the gravitational acceleration g=9.81 m/s2.
  4. Trapezoid
    hexphitri Area of trapezoid is 135 cm2. Sides a, c and height h are in a ratio 6:4:3. How long are a,c and h? Make calculation...
  5. Divers
    diving 20-member group of divers carries the air for 15 hours of diving. 4 members of the expedition sick or wasn't came. How many hours is sufficient air to other divers?
  6. Lorry
    lorry The lorry was loaded with 18 boxes of 15 kg. How many boxes with weight 18 kg can be loaded, if total load must be same?
  7. Grandson and granddad
    vnuk_dedo Grandson with grandpa they counted how many years have together. Their product is 365. How many years is the sum of their years.
  8. 30-60-90
    30-60-90 The longer leg of a 30°-60°-90° triangle measures 5. What is the length of the shorter leg?
  9. Iron fence
    fe One field of iron fence consists of 20 iron rods with square cross-section of 1.5 cm side and a long 1 meter. How much weight a field if the density of iron is 7800 kg/m3.
  10. Two cars
    TwoCars From the town A to town B started two cars. The first at 7:00 at average speed 60 km per hour, the second at 10:00 at average speed 100 km per hour. The first car will not stay in B, and on the way back meet the second car at half way from A to B. At what.
  11. Racer
    car_championship The first racer run at a speed 20 m/s and is 750 meters before the finish and ahead 79 meters before second competitor. At what speed must run the second racer to catch first racer at the finish line?
  12. Strawberries
    strawberries Father collects strawberries himself in 4 hours, son in 14 hours. How long will it take them along when dad comes to help son collect strawberries after 3 hours?
  13. Sawdust
    drevo_kmen_rez How many cubic centimeters of wood sawdust is created by cut the tree trunk with a diameter of 66 cm and when the gap width is 5 mm?
  14. Pyramid
    3d_shapes Cuboid ABCDEFGH has dimensions AB 3 cm, BC 4 cm, CG 5 cm. Calculate the volume and surface area of a triangular pyramid ADEC.
  15. Chicken
    sliepka I threw three chicken for a handful of grains and I noticed that it eat in a ratio of 8:7:6 and two of them grabbed 156 grains. How many grains have fought that chicken?
  16. Unions
    odbory_prdel Calculate how much money per year would go to the treasury of unions if 218 thousand employee join unions with an average net salary of 407 euros and if memberhip in union cost 1% of the net monthly salary.
  17. Painter 3
    painter_2 Dad want to paint wall high 250 cm wide and 230 cm with wallpaper. How many meters must buy wallpaper if wallpaper width is 60 cm?
  18. Cube and water
    krychle_3 How many liters of water can fit into a cube with an edge length of 0.11 m?
  19. Flowerbed 2
    flowerbed Around the square flower bed in a park is sidewalk 2 m wide. The area of ​​this sidewalk is 243 m2. What is the area of the flowerbed?
  20. Cuboids in cube
    shapes How many cuboids with dimensions of 6 cm, 8 cm and 12 cm can fit into a cube with side 96 centimeters?

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