Examples for 8th grade - page 28

  1. Parallelogram
    quadrilateral_parallelogram The perimeter of the parallelogram is 117 cm. The length of one side is 1.9-times longer than the length of the shorter side. What is the length of sides of a parallelogram?
  2. Sisters
    sisters Sisters Hanka and Vera goes mostly tograndmother by bicycle. Journey took Hanka 30 minutes and Vera 20 minutes. How long will Vera catch up with Hanka when started from home five minutes later than Hanka?
  3. Around the flowerbed
    roses Around a rectangular flowerbed with dimensions 5.25 m and 3.5 m are to be planted roses equally spaced so that the roses found in every corner of the flowerbed and consumed them as little as possible. a) At what distance are planted roses? b) How many ros
  4. Components
    components In the box are 8 white, 4 blue and 2 red components. What is the probability that we pull one white, one blue and one red component without returning?
  5. Wood
    rubanie_dreva Peter chops wood. If they cut down a half hours a day he ended work in 9 days. But Peter needs to end work 3 days earlier. How many minutes a day should cut down?
  6. Diameter
    diameter_circle If the endpoints of a diameter of a circle are A(1, 7) and B (-1, -7), what is the radius of the circle?
  7. Temperature calculus
    snowman Calculate percentage of temperature decrease if changed from -5 °C to -16 °C?
  8. Vacation
    motion Parents piggybacking children on vacation to its grandmother and grandfather at a city distant 150 kilometers. They agreed to meet halfway. Parents will be travel at 90 km/h, grandmother and grandfather at 60 km/h. Parents depart at 12:00 hours. When grand
  9. Tablecloth
    decka I embroider tablecloth in 20 days but if I embroider 3/4 hours a day I have embroider it for 15 days. How long do I embroider a day?
  10. Journey
    Mt-Everest The road from A to B measures 11.5 km. Firstly up the hill, then by level plane and then downhill. Tourist goes uphill at 3 km/h, on the plane 4 km/h and downhill 5 km/h. From point A to B went 2h 54 min back 3h 6 min. How long is the segment of level pla
  11. RT 11
    right_triangle Calculate the area of right tirangle if its perimeter is p = 45 m and one cathethus is 20 m long.
  12. Paper box
    cuboid_5 Calculate the consumption of paper on the box-shaped quadrangular prism with rhombic footstall, base edge a=6 cm and the adjacent base edges forms an angle alpha = 60 °. Box height is 10 cm. How many m2 of the paper consumed 100 such boxes?
  13. Roller
    cestnyvalec Roller has a diameter of 0.96 m and a width 169 cm. How many m2 of road level when he turns 42-times?
  14. IS trapezoid
    el_trapezium Isosceles trapezoid arm measured 35 cm. Height is 30 cm and middle segment is 65 cm. Determine length of its bases.
  15. Aircraft
    aircraft_soviet The aircraft has in a fuel tank 68 hl of aviation fuel and flight consumes 3.6 liters of fuel. Identify the function, which expresses the dependence of the volume of fuel in tank on the track distance plane flew by. How many hectolites of fuel is still in
  16. Two typists
    lasica_typewriter There are two typists who are rewriting the material 814 pages. First can it handle rewrite yourself for 24 days; the second 12 days. First typist wrote material yourself 4 days rest rewrites yourself second typist. How many days will it take rewriting alt
  17. Angles ratio
    3angle_1 In a triangle ABC true relationship c is less than b and b is less than a. Internal angles of the triangle are in the ratio 5:4:9. The size of the internal angle beta is:
  18. Estate
    mapa Estate shaped rectangular trapezoid has bases long 34 m , 63 m and perpendicular arm 37 m. Calculate how long is its fence.
  19. Farmer
    krava The farmer farming 293 ha of arable land and the remaining 20% are meadows and pastures. How much land farmer owns?
  20. Angles in triangle
    trigonometry The triangle is ratio of the angles β:γ = 6:8. Angle α is 40° greater than β. What are the size of angles of the triangle?

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