Examples for 8th grade - page 49

  1. Rectangle
    obdelnik The width of the rectangle is 65% of its length. Perimeter of the rectangle is 132 cm. Determine the dimensions of the rectangle.
  2. Diplomas
    diploma Suzanne helped write out diplomas. Issuance its first took 3 minutes, each next 2.3 minutes. How much time it will take to write out n=16 diplomas (including the first), write out this pace?
  3. Equilateral triangle v2
    eq_triangle Equilateral triangle has a perimeter 36 dm. What is its area?
  4. Right triangle trigonometrics
    triangle2 Calculate the size of the remaining sides and angles of a right triangle ABC if it is given: b = 10 cm; c = 20 cm; angle alpha = 60° and the angle beta = 30° (use the Pythagorean theorem and functions sine, cosine, tangent, cotangent)
  5. Cyclist
    cyklista Cyclist rode two-fifths of the way the first day. The second day drove 5 km less while traveled three-eighths of route. How many kilometers does he have to finish target?
  6. 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.
  7. Hexa prism
    hexagon Determine the volume of hex prism with edge base 4 cm. The body height is 28 cm.
  8. 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.
  9. 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
  10. 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?
  11. Circle inscribed
    inscribed345 Calculate the perimeter and area of a circle inscribed in a triangle measuring 3 , 4 and 5 cm.
  12. 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?
  13. 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.
  14. 9-gon
    9gon Sum of interiol angles of 9-gon is:
  15. 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?
  16. Cube 7
    krychle_4 Calculate the volume of a cube, whose sum of the lengths of all edges is 276 cm.
  17. 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.
  18. Cuboid walls
    cuboid_9 Calculate the volume of the cuboid if its different walls have area of 195cm², 135cm² and 117cm².
  19. Children
    weight_1 Margaret and Zdena weighs the same and Petra 3 kg more. Together weigh 156 kg. How much does they weigh?
  20. 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?

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