Examples for 8th grade - page 42

  1. Cups
    pohare We have three cups. In the cups we had fluid and boredom we started to shed. 1 We shed one-third of the fluid from the second glass into the first and third. 2 Then we shed one quarter cup of liquid from the first to the second and to the third. 3 Then
  2. Barrel with liquid
    barrel Barrel with grain weight 297 kg. When it shed 48% of grain, ha weight 174 kg. What is the weight of empty barrel?
  3. Ski lessons
    skiing_2 On the ski course leaves 80 pupils. They live in triple and quadruple rooms. Count if rooms is the 23. How many are triple and quadruple rooms?
  4. Floating floor
    floor In the new building is considered a floating floor worker in each room. 30 minutes lay 9 m2 of the floor. How long 3 workers laid the floor in 4 rooms with a total area of 90 m2?
  5. Tetrahedral prism
    hranol_1 The height of a regular tetrahedral prism is three times greater than the length of the base edge. Calculate the length of the base edge, if you know that the prism volume is 2187 cm3.
  6. Equation with fractions
    go Solve equation: ? It is equation with fractions.
  7. Aircrafts
    boeings Above the town hall tower flew the plane with constant speed 592 km/h and 15 minutes later the second plane at speed of 675 km/h. How long and how far from the town hall will be aircrafts caught up?
  8. Bottles of juice
    juice_cones How many 2-liter bottles of juice need to buy if you want to transfer juice to 50 pitchers rotary cone shape with a diameter of 24 cm and base side length of 1.5 dm.
  9. Stairs
    schosy Between adjacent levels are 15 stairs. If step will be 1.2 cm lower there would be 16 stairs. What is the stair height?
  10. Prism
    prism The volume of tetrahedral prism is 2.43 m3. Base of prism is a parallelogram in which a side 2,5dm and height ha = 18cm. Calculate the height of the prism.
  11. Inflow - outflow
    water_barrels The tank will fill by inflow for 143 minutes and empties by outflow for 150 minutes. How long take to fill tank if it is also opened the inflow and outflow?
  12. Percentage of waste
    14 In a square plate with side 75 cm we cut 4 same circles. Calculate the percentage of waste.
  13. Bank deposit
    bank_1 Ms Jana after the withdraw amount of 2,500 euros after year saving in bank. What was her deposit if the interest rate was 2.5% p.a..
  14. Garage
    garaz2 There are two laths in the garage opposite one another: one 2 meters long and the second 3 meters long. They fall against each other and stay against the opposite walls of the garage and both laths cross 70 cm above the garage floor. How wide is the garag
  15. Cars motion
    AB From point A car start at the speed of 90 km/h. Against it departs from the point B at the same time another car at 60 km/h. For how long and where they met if the distance between A and B is 180 km?
  16. Slope
    lines.JPG Calculate the slope of a line that intersects points (-84,41) and (-76,-32).
  17. Wood
    timber Wood contains 12% water. 1 m3 of wood weighs 650 kg. How many liters of water it contains?
  18. The cylindrical container
    cylinder_1 The container has a cylindrical shape the base diameter 0.8 meters has a content area of the base is equal to the content area of the shell. How many full liters of water can be poured maximally into the container?
  19. Roots
    square_roor Calculate the square root of these numbers:
  20. The dam
    prehrada-orlik The water reservoir is filled with first tributary for 25 hours second tributary for 35 hours. Some time were both inlets open, then a second tributary closed and the tank was filled in four hours. What time water flowed from both tributaries? (Expressed i

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