Examples for 8th grade

  1. Chord circle
    tetiva2 The circle to the (S, r = 8 cm) are different points A, B connected segment /AB/ = 12 cm. AB mark the middle of S'. Calculate |SS'|. Make the sketch.
  2. Repairman
    makak Repairman has vowed to do repair work at the plant for 25 days. However work had to be shortened, and therefore he took helper worker. Together they made all the corrections for the whole days. How long it would take work to helper worker?
  3. Buttons
    knofliky Shirt has 6 buttons, blouse has 4 buttons. All buttons are 176. Shirts and blouses are together 36. How many are the shirts and blouses?
  4. Triangular pyramid
    tetrahedron1 Calculate the volume and surface area of a regular triangular pyramid whose height is equal to the length of the base edges 10 cm.
  5. Hiker and cyclist
    cyklo At 7 PM hiker started at 6 km/h to hike. After 3 hrs. later started on the same trip cyclist at speed of 15 km/h. After an hour of driving a flat tire and take him half hours to correct defect. At what time catch up cyclist with hiker?
  6. MO - triangles
    metal On the AB and AC sides of the triangle ABC lies successive points E and F, on segment EF lie point D. The EF and BC lines are parallel and is true this ratio FD:DE = AE:EB = 2:1. The area of ABC triangle is 27 hectares and line segments EF, AD, and DB s
  7. Umbrella
    dazdnik Can umbrella 75 cm long fit into a box of fruit? The box has dimensions of 390 mm and 510 mm.
  8. Tickets
    stadion_1 On the football tournament ticket cost 45 Kc for standing and 120kč for sitting. Sitting spectators was 1/3 more than standing. The organizers collected a total 12 300 Kc. How many seated and standing seats (spectators)?
  9. Cube 9
    MD_cheese_cubes What was the original edge length of the cube if after cutting 39 small cubes with an edge length 2 dm left 200 dm3?
  10. Park
    diamond_3 In the park is marked diamond shaped line connecting locations A, D, S, C, B, A. Calculate its length if |AB| = 108 m, |AC| = 172.8 m.
  11. Family
    sediny Mom is 39 years old. Karl is eight years and Paul 4 years. For many years mother would old just like two children together?
  12. Reciprocal equation
    img_reci_1 Determine the root of the equation: 9/x-7/x=1
  13. Acreage
    parcela What acreage has a rectangular plot whose diagonal is 34 meters long and one side has a length of 16 meters. ?
  14. Dog
    stvorec_1 Dog is tied to a chain, which is mounted in a corner of the yard. Yard has the shape of a square with a side length of 20 meters. The same long is also dogchain. Are there places in the yard where dog can't reach?
  15. Trio 2
    decide Decide whether trio of numbers is the side of a right triangle: 26,24,10.
  16. Hypotenuse
    sqrt Calculate the length of the hypotenuse of a right triangle with a catheti 71 cm and 49 cm long.
  17. Rhombus 4
    diamond_shape Circumference of the rhombus is 44 cm, its height is 89 mm long. Calculate its content area.
  18. Backpack
    batoh_1 Large backpack cost CZK 1352, little is 35% cheaper. How much we paid for 5 large and 2 small backpacks?
  19. Journey to school
    steps_3 On the way to school I went steady step. In the first half of the journey, I counted every second step, in the second half every third. How many steps I do when I went to school if I counted double step are 250 more than three steps?
  20. Joshka
    money-false Joshka had € 15. Mama took him 15%. How many had left?

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