Examples for 8th grade - page 15

  1. Slope
    slope What is the slope of a line with an inclination 52°?
  2. KLMN
    trapezium In the trapezoid KLMN is given this informations: 1. segments KL and MN are parallel 2. segments KL and KM has same length 3. segments KN, NM and ML has same length. Determine the size of the angle KMN.
  3. Discounts on rail (ZSSK)
    preukazy_zssk The railway company ZSSK offers a discount of 40% (JUNIOR RAILPLUS EURO
  4. Wood in the forest
    drevo The amount of wood in the forest was estimated at 24000 m3. How much wood will be in forest after 3 years if the annual growth of wood is 3% each year and logging 360 m3 each year?
  5. The chord
    Tetiva Side of the triangle inscribed in a circle is a chord passing through circle center. What size are the internal angles of a triangle, if one of them is 40°?
  6. Train
    High-Speed-Train A passenger train traveled for 4 hours 136 km. 2.7 hours after its departure started fast train and caught it on 324 km. How many km/h is different its average speeds?
  7. Lead cube
    pb_cube Calculate the edge of the cube made ​​from lead, which weighs 11 kg. The density of lead is 11341 kg/m3.
  8. Cylinder - h
    cylinder_2 Cylinder volume is 129 cm3. Base radius is 3 cm. Calculate the height of the cylinder.
  9. Barrel 3
    sud-s-vodou Barrel with water has a weight 118 kg. When we get off 75% of water it has a weight 35 kg. How many kg has empty barrel?
  10. Stock market
    money_1 Simon one day decided to invest € 88000 to the stock market. After six months he invested July 5 stock markets fell by 56%. Fortunately for Simon from July 5 5 to October 5 his shares have risen by 39%. Simon is then: ?
  11. Height
    thales_law Is right that in any right triangle height is less or equal half of the hypotenuse?
  12. Rhombus
    rhombus2 Internal angles of rhombus is in ratio 3:6. How many times is the shorter diagonal longer than side of rhombus?
  13. Parallelogram
    paralleogram Calculate area of the parallelogram ABCD as shown if |AB| = 45 cm, |BC| = 23 cm and angle BAD = 30°
  14. Wire D
    semicircle_1 Wire length 5 m is bent so that it forms a semicircle circuit (including the diameter). Determine the radius of the semicircle.
  15. Tea blend
    teas Tea blends are maked from two kinds of tea. In standard tea mixture are two teas in the ratio 1:3 and 40 g costs 42 CZK. In the premium tea mixture are weighing two teas in the ratio 1:1 and 50 grams costs 60 CZK. How much cost 10 grams of more expensive k
  16. Pentagon
    5gon_1 Within a regular pentagon ABCDE point P is such that the triangle is equilateral ABP. How big is the angle BCP? Make a sketch.
  17. Arm
    arm Calculate the length of the arm r of isosceles triangle ABC, with base |AB| = 16 cm and a height v=10 cm.
  18. Division
    bonbons Three siblings Helena, Oliver and George split the bag with candies on merit in the ratio 1:6:3. How many candies should each get if in bag were 210?
  19. Triangle in circle
    triangle_in_circle Vertices of the triangle ABC lies on a circle with radius 6 so that it is divided into three parts in the ratio 3:2:5. Calculate the circumference of the triangle ABC.
  20. Prism
    prism-square The lenght, width and height of a right prism are 18, 14 and 9 respectively. What is the lenght of the longest segment whose endpoints are vertices of the prism?

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