Examples for 8th grade - page 33

  1. Stone
    kamen When Peter threw stone in a box of water he discovered that the water level has risen by 8 cm. The box has a cuboid shape, the bottom has dimensions of 24 cm and 14 cm, height is 48 cm. What volume has a stone?
  2. Arc
    vysek What area of a circle occupied the flowers planted in the arc of a circle with radius 2 m with central angle 45°?
  3. angles in quadrilateral
    4uhelnik What size have angles in quadrilateral (4-gon) if they are in a ratio of 8: 9: 10: 13?
  4. Truck
    auto In 7 hours started from town Krnov truck at speed 40 km/h. Passenger car started against it in 8 hours 30 minutes from the city of Jihlava at speed 70 km/h. Distance between this two cities is 225 km. At what time and at what distance from Krnov this two.
  5. Salt
    sol 1 t of sea water contains 25 kg of salt. How many tons of seawater must be evaporated to obtain 2 q of salt?
  6. Seamstress 2
    krajcirka_1 Seamstress bought two kinds of textile in whole meters. One at 50 SKK and the second 70 SKK per meter. How many meter bought from this two textiles when paid totally 1540 SKK?
  7. Plan of the village
    mapa_1 Plan of the municipality in 1:1000 scale has plotted garden with dimensions 25 mm and 28 mm. Determine the area of gardens in ares in reality.
  8. Mother and daughter 2
    mother_baby The mother is 40 years older than her daughter. How old is the mother if her age is eight thirds age of daughter?
  9. Sportsman
    lungs A trained athlete is able to exhale after a deep breath still 500 ml of air. At normal inhalation and exhalation is breathing 500 ml of air. Within one minute, one breath and exhaled 19 times. What part of breathing air per day is one exhalation?
  10. Tachometer
    tatra-dakar2 Tatra's tachometer shows the initial state 154009 km this morning. Tatra today travel at an average speed of 35 km/h. Determine the function that describes the Tatra's tachometer depending on the time. What is the state of tachometer after 4.8 hours?
  11. Complementary angles
    angles_2 Two angles are complementary. If one angle measures 49°, what is the measure of the second angle?
  12. Rectangle
    rectangle_inscribed_circle The rectangle is 36 cm long and 48 cm wide. Determine the radius of the circle circumscribing rectangle.
  13. Quadrant
    quadrants In what quadrant is a 1501° angle?
  14. Bath
    bathroom In the bath is 30 liters of hot water. Then added 38 liters of cold water at temperature of 17 °C decreased temperature of water to 48 °C. What was the initial temperature of the hot water?
  15. Freedom
    family_life In the city are 2/6 of women married for 4/4 men. What proportion of the townspeople is free (not married)? Express as a decimal number.
  16. Fraction
    polynomial For what x expression ? equals zero?
  17. Raffle
    tombola_tickets In the pool is numbers from 1 to 135. What is the probability that a randomly selected number is not a prime number?
  18. Heron backlaw
    heron_math Calculate missing side in a triangle with sides 33 and 27 and area 118.3.
  19. The cyclist
    cyclist The cyclist went from village to town. First half of journey went at 19 km/h. The second half of the journey, which mostly fell, went at 33 km/h. All journey took 67 minutes. Calculate the distance from the village to the town.
  20. Skiing meeting
    compass4 On the skiing meeting came four friends from 4 world directions and led the next interview. Charles: "I did not come from the north or from the south." Mojmir "But I came from the south." Joseph: "I came from the north." Zdeno: "I come from the south." W

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