Examples for 8th grade - page 68

  1. Triangle
    heron1 Determine whether a triangle can be formed with the given side lengths. If so, use Heron's formula to find the area of the triangle. a = 158 b = 185 c = 201
  2. Unions now
    roh The plant has 1,250 employees. The Trade Unions (former ROH, OH) is 18% male, 23% female. Plant management reported that in the trade union is 20% of all employees. How many men and women are in plant and how many are men and women in trade unions?
  3. Ice and water
    ice_playground We want to cover rectangular rink with dimensions of 55 m and 25 m with 4cm thick layer of ice. How many liters of water we need if after freezing water increases its volume by 10%?
  4. Average mark
    flag_english Calculate average mark in English, if a student got a couple of 3's, 20% less 2 than 3, and 50% more 1's than the 2's.
  5. Pigs
    prasce Pigs are feed by beet.Beet feed containing 12% dry solids, which is 0.72% of digestible crude protein. How much beet must beconsumed in one month (30 days), if the weight of digestible crude protein contained in a daily dose of beet was 0.912 kg?
  6. Fe vs. H2O
    atoms_Fe The volume of what the body of the same weight is greater - iron or water?
  7. Five-digit
    cards Find all five-digit numbers that can be created from numbers 12345 so that the numbers are not repeated and then numbers with repeated digits. Give the calculation.
  8. Cuboid box
    box How many m2 paper is needed for the sticking cuboid box of dimensions 50 cm, 40 cm and 30 cm? To the folds add one-tenth the area.
  9. Annulus
    medzikruzie Calculate the area of two circles annulus k1 (S, 3 cm) and k2 (S, 5 cm).
  10. Testing
    test_3 Students of high school have 10 points for each good solved task. The wrong answer is deducted by 5 points. After solving 20 tasks, student Michael had 80 points. How many tasks did he solve correctly and how many wrong?
  11. Broken tree
    broken_tree The tree was 35 meters high. The tree broke at a height of 10 m above the ground. Top but does not fall off it refuted on the ground. How far from the base of the tree lay its peak?
  12. Dealer
    canon Dealer sell digital camera for € 474. Thirty percent of the price was his profit. After some time, decreased interest in selling the camera and therefore reduce its sales price by 11 %. How many percent of the new price now is dealer's profit? Round the
  13. Math heart
    srdce_1 Stylized heart shape created from a square with side 5 cm and two semicircles over his sides. Calculate the content area and its circumference.
  14. Locomotive
    locomotive_1 Locomotive pulled a train permanent load of 200 kN horizontally along the track of 5km. What work it done?
  15. Right triangles
    PT How many right triangles we can construct from line segments 3,4,5,6,8,10,12,13,15,17 cm long? (Do not forget to the triangle inequality).
  16. Clock Tower
    clock_3 What angle is betwenn hands on Clock Tower when show 17 hours and 35 minutes?
  17. Water lake
    jezirko The length of the lake water is 8 meters width 7 meters and depth 120 centimeters. How many liters of water can fit into the water lake?
  18. Pages of book
    books_2 Lenka calculated that if every day to read 16 pages of the book, read a book a day earlier than had read only 14 pages a day. How many pages has this book?
  19. Product - quadratic equation
    circles_3 Product of two numbers is 900. If we increase lowest number by 2 then product will increase by 150. Determine both numbers.
  20. Hostel
    student Students are accommodated in 22 rooms. Rooms were 4 and 6 bed. How many rooms in which type occupied 106 children there?

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