Examples for 8th grade - page 41

  1. Acreage
    parcela What acreage has a rectangular plot whose diagonal is 34 meters long and one side has a length of 16 meters. ?
  2. Deposit 3
    interest_money After a year had Martin on bank account € 1764. What was the interest rate when the initial deposit was € 1581?
  3. Inscribed triangle
    obluk To a circle is inscribed triangle so that the it's vertexes divide circle into 3 arcs. The length of the arcs are in the ratio 2:3:7. Determine the interior angles of a triangle.
  4. 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?
  5. Alloy
    hlinik_slitina The first alloy is a mixture of two metals in the ratio 1:2, the second is a mixture of same metals in the ratio 2:3. At what ratio we have these two alloys put into the furnace to obtain a new metal alloy with ratio 17:27? (All three ratios correspond to.
  6. Vinegar
    vinegar_1 What percentage vinegar we get if we mix 1 if dm³ eight percent vinegar with 1.5 dm³ six percent vinegar?
  7. Tree
    strom How tall is the tree that observed in the visual angle of 52°? If I stand 5 m from the tree and eyes are two meters above the ground.
  8. Silo
    silo Outer perimeter of silo is 24 m. Concrete wall is 18 cm thick. What is diameter and area of inside floor of silo?
  9. Three-digit numbers
    poker_hand_ranking How many three-digit numbers are from the numbers 0 2 4 6 8 (with/without repetition)?
  10. Diagonal in rectangle
    q In that rectangle ABCD is the center of BC point E and point F is center of CD. Prove that the lines AE and AF divide diagonal BD into three equal parts.
  11. Roots
    square_roor Calculate the square root of these numbers:
  12. Decomposition
    prime_factorization Make decomposition using prime numbers of number 355. Result write as prime factors (all, even multiple)
  13. Water level
    hladina.JPG How high reaches the water in the cylindrical barell with a diameter of 12 cm if there is a liter of water? Express in cm with an accuracy of 1 decimal place.
  14. Cylinder - h2
    valec_1 Cylinder volume is 2.7 liters. Base area is 1 dm2. Calculate the height of the cylinder.
  15. Slope
    lines.JPG Calculate the slope of a line that intersects points (38,-23) and (-93,5).
  16. Diamond
    diamond_1 Rhombus has side 23 cm and and one of diagonal 36 cm long. Calculate its area.
  17. Daughters
    family_3 The man conducting the census asks a woman to age of three daughters. Woman says when multiply the age getnumber 72; if their ages add up, get a number of our house, as you see. The man says: That is not enough to calculate their ages. She says: my oldes
  18. Quadrilateral
    diamond_2 In the square ABCD point P is in the middle of the DC side and point Q in the middle pages AD. If the area of quadrilateral BQPC is 96 cm2, what is the area of ABCD?
  19. Lie/do not lie
    lines_and_points The function is given by the rule f(x) = -x-12. Determine whether point D[-4; 2] lies on this function. Solve graphically or numerically and give reasons for the your answer.
  20. Class 8.A
    trieda_2 Three quarters of class 8.A went skiing. Of those who remained at home one third was ill and the remaining six were on math olympic. How many students have class 8.A?

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