Examples for 8th grade - page 22

  1. Cuboid
    cuboid_3 Cuboid ABCDEFGH with 10 cm height has a base edge length 6 cm and 8 cm. Determine angle between body diagonal and the base plane (round to degrees).
  2. Rhombus HP
    rhombus3_1 Calculate area of the rhombus with height 21 m and perimeter 20 m.
  3. Two workers
    Frog Two workers together execute some work in 10 days. The first worker would have done himself in 20 days. How many days would have done himself a second worker?
  4. Icerink
    klzisko-korcule Rectangular rink with dimensions of 69.3 m and 567 dm must be covered with a layer of ice 2.9 cm thick. How many liters of water is necessary for the formation of ice when the volume of ice is 10.2% greater than the volume of water.
  5. Tetrahedral prism
    hranol Calculate surface and volume tetrahedral prism, which has a rhomboid-shaped base, and its dimensions are: a = 12 cm, b = 7 cm, ha = 6 cm and prism height h = 10 cm.
  6. Circumferential angle
    uhly Vertices of the triangle ΔABC lies on circle and divided it into arcs in the ratio 5:3:10. Determine the size of the angles of the triangle ΔABC.
  7. Tractors
    tractor_2 Six tractors plowing the field for 8 days. After two days, two tractors broke down. How many days were prolonged work in the field?
  8. Triangle TBC
    isosceles_triangle TBC is isosceles triangle with base TB with base angle 63° and legs length |TC| = |BC| = 25. How long is the base TB?
  9. Rectangle diagonals
    rectangle_diagonals_1 It is given rectangle with area 24 cm2 a circumference 20 cm. The length of one side is 2 cm larger than length of second side. Calculate the length of the diagonal. Length and width are yet expressed in natural numbers.
  10. Pizza
    pizza_1 A school survey found that 10 out of 11 students like pizza. If 6 students are chosen at random, what is the probability that all 6 students like pizza?
  11. ISO trapezium
    trapezium_2 Calculate area of isosceles trapezoid with base 95 long, leg 27 long and with the angle between the base and leg 70 degrees.
  12. Rectangle
    rectangles_1 The perimeter of the rectangle is 22 cm and content area 30 cm2. Determine its dimensions, if the length of the sides of the rectangle in centimeters is expressed by integers.
  13. 9.A
    exam 9.A to attend more than 20 students but fewer than 40 students. A third of the pupils wrote a math test to mark 1, the sixth to mark 2, the ninth to mark 3. No one gets mark 4. How many students of class 9.A wrote a test to mark 5?
  14. Trains for people
    757_rusen It is said that the train is synonymous to delay. Calculate the average speed of travel by train long 19 km, with regular train leave at 5:47 and arrive at 6:13, but train is late and has departure at 9:01 and arrive at 9:25.
  15. Two runners
    sprinters_1 Two runners ran simultaneously towards each other from locations distant 34.6 km. The average speed of the first runner was 1/5 higher than the average speed of the second runner. How long should each ran a 34.6 km, if you know that they meet after 67 mi
  16. Apartments
    panelak Apartment on the first floor was 10% more expensive than the same apartment on the second floor. The difference was 105 Kc annually. Calculate the annual rent of the apartment in the first floor and from apartment on the second floor.
  17. Degrees to radians
    angle Convert magnitude of the angle α = 9°39'15" to radians:
  18. Concrete pipe
    concrete_pipe Concrete pipe is cylindrical with an inner diameter 110 cm and outer 120 cm. Calculate the surface of the concrete pipe, if it is 9 m long.
  19. Map - climb
    Lanovka_na_skalnate_pleso On the map of High Tatras in scale 1:11000 are cable car stations in the Tatranska Lomnica and in the Skalnate Pleso with distance 354.6 mm. Altitude of this stations are 949 m and 1760 m. What is average angle of climb of this cable car track?
  20. Height
    equilateral_triangle Calculate height of the equilateral triangle if its perimeter is 8?

Do you have interesting mathematical example that you can't solve it? Enter it and we can try to solve it.

To this e-mail address we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.