Examples for 8th grade - page 50

  1. Tangents construct
    tecna Circle is given k (S; 2.5 cm) and an outer line p. Construct a tangent t of the circle that has with a line p angle 60°. How many solutions has the task?
  2. Trapezoid thirds
    lichobeznik_mo_z8_3 The ABCD trapezoid with the parallel sides of the AB and the CD and the E point of the AB side if the segment DE divides the trapezoid into two parts with the same area. Find the length of the AE line segment.
  3. Hexa prism
    hexagon Determine the volume of hex prism with edge base 4 cm. The body height is 28 cm.
  4. Nectar
    vcela Nectar collected by bees contains 70% water. From the nectar of the some process produces honey which contains 19% water. How many kg of nectar bees need to collect to make 1 kg of honey?
  5. Two numbers
    third The sum of two numbers is 1. Identify this two numbers if you know that the half of first is equal to the third of second number.
  6. Circle inscribed
    inscribed345 Calculate the perimeter and area of a circle inscribed in a triangle measuring 3 , 4 and 5 cm.
  7. Truck PRG-BA
    kamionka Truck driving on highway from Prague to Bratislava at average speed of 72 km/h. At the moment when the truck passes 54 kilometer from Prague passenger car departs from Prague which travel to Bratislava at speed 90 km/h. When and where (at waht highway ki
  8. Cottages
    chatky The summer camp is 41 cottages. Rooms are for three and for four in them. How many of the 140 campers lives of three?
  9. Is right triangle
    rt.JPG One angle of the triangle is 36° and the remaining two are in the ratio 3:5. Determine whether triangle is a rectangular triangle.
  10. 9-gon
    9gon Sum of interiol angles of 9-gon is:
  11. Cube 7
    krychle_4 Calculate the volume of a cube, whose sum of the lengths of all edges is 276 cm.
  12. Silver medal
    circle_1 To circular silver medal with a diameter of 10 cm is inscribed gold cross, which consists of five equal squares. What is the content area of silver part?
  13. Cylinder
    cyl_1 The cylinder-shaped container has 80 liters of water. The water reaches 45 cm height. How many liters of water will be in a container if water level extend to a height 72 cm? Write the result in liters, write down only as a whole or decimal number.
  14. Children
    weight_1 Margaret and Zdena weighs the same and Petra 3 kg more. Together weigh 156 kg. How much does they weigh?
  15. Car consumption
    motor The car has consumption 4 l/100 km. How much money will it cost ride 4 km in long if diesel price is 1.53 USD/l?
  16. Cuboid walls
    cuboid_9 Calculate the volume of the cuboid if its different walls have area of 195cm², 135cm² and 117cm².
  17. Janitor
    snow Janitor tosses 26 cm layer of snow on the school grounds for 90 minutes. How many friends would have to call for help if snow needs to have bowled for 15 minutes. We assume that at the same time bow all the same amount of snow.
  18. Seamstress
    krajcirka Seamstress bought two kinds of textile together 25 meters. One at 50 SKK and the second 70 SKK per meter. How many meter bought from this two textiles when paid totally 1540 SKK?
  19. 12 Moons
    12_mesicku Good Marry came to ask twelve moons for help with collecting strawberries. All twelve moons 1200 strawberries picked in 20 minutes. But lazy months July and August cease tear after 5 minutes. How many minutes in total will take collect strawberries?
  20. Angles of a triangle
    triangles_9 In the triangle ABC, the angle beta is 15° greater than the angle alpha. The remaining angle is 30° greater than the sum of the angles alpha and beta. Calculate the angles of a triangle.

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