Examples for 8th grade - page 84

  1. Equilateral triangle
    rs_triangle_1 The equilateral triangle has a 23 cm long side. Calculate its content area.
  2. Liters od milk
    milk_cylinder The cylinder-shaped container contains 80 liters of milk. Milk level is 45 cm. How much milk will in the container, if level raise to height 72 cm?
  3. Square
    ctverec_1 Danov's father has a square of 65.25 milligram square of wire with a diagonal. How will the square be big when one mm weighs 7 mg?
  4. Friends
    Auticka James and Jaroslav are friends. Together they had 48 toy cars. But if John took 8 cars from Jaroslav, Jaroslav will be have 1.5 times more toy cars than James. How many toy cars had Jaroslav and James?
  5. Runner 2
    runner2 Marian run 12 meters in 8 seconds. How far would Marian run for 70 seconds, if still run at the same pace?
  6. Cylinder
    cylinder_6 In a 1-meter diameter cylinder is 1413 liters of water, which is 60% of the cylinder. Calculate the cylinder height in meters, do not write the units. The resulting value round and write as an integer.
  7. Truck and car
    smetiari At 6h45min the truck started at a speed of 36 km/h. At 7h30m behind it a passenger car. Find the average speed of passenger car if it will catch truck 72 km away from the factory.
  8. Mushrooms
    huby_3 Fresh mushrooms contain 90% water, dried only 12%. How many kilograms of fresh mushrooms are needed for 5kg dried?
  9. Sawmill factory
    rj Peter works in the factory. The bus stop is 10 km from the factory. Therefore, always when the bus arrives for Peter, the driver leaves factory and takes him to work. They are coming at the saw exactly at 8:00. Today the bus arrived 11 minutes earlier and.
  10. EQ2
    eq2_4 Solve quadratic equation: ?
  11. Parallelogram
    kosostvorec_3 Side a of parallelogram is twice longer than side b. Its circumference is 78 dm. Calculate the length of the sides of a parallelogram.
  12. Unknown number 4
    ninth I think number. When I divided its square root by its 1/9, I get a number 1. What number am I thinking?
  13. Class
    children_2 In a class are 32 pupils. Of these are 8 boys. What percentage of girls are in the class?
  14. Football match 4
    futball_ball In a football match with the Italy lost 3 goals with Germans. Totally fell 5 goals in the match. Determine the number of goals of Italy and Germany.
  15. Backpack
    batoh_1 Large backpack cost CZK 1352, little is 35% cheaper. How much we paid for 5 large and 2 small backpacks?
  16. Rectangle
    rectangles_11 Find the dimensions of the rectangle, whose perimeter is 108 cm and the length is 25% larger than the width.
  17. Workers
    okno2_1 Group of workers washing half of the windows of the building in two hours. How long will take half the workers wash all the windows of the building?
  18. Outer contact of circles
    nakres_2z Construct a circle k1 (S1; 1.5 cm), k2 (S2; 2 cm), and K3 (S3; 2.5 cm) so that they are always two outer contact. Calculate the perimeter of the triangle S1S2S3.
  19. Three monks
    Bible Three medieval monks has task to copy 600 pages of the Bible. One rewrites in three days 1 page, second in 2 days 3 pages and a third in 4 days 2 sides. Calculate for how many days and what day the monks will have copied whole Bible when they begin Wednesd
  20. Ladder
    rebrik_3 Ladder 10 meters long is staying against the wall so that its bottom edge is 6 meters away from the wall. What height reaches ladder?

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