Examples for 8th grade - page 42

  1. Principal and interest
    bank_pig Peter put € 270 principal into bank and at the end of the year on account was € 282. To what annual interest rate that Peter had deposited money in the bank?
  2. Sugar
    cukr Sugar factory produced 938.1 tons of sugar in 1 day at 14% sugar content . How many tons of pure beet sugar factory processed in 1 day?
  3. Hexagonal pyramid
    hexagonal-pyramid Base of the pyramid is a regular hexagon, which can be circumscribed in a circle with a radius of 1 meter. Calculate the volume of a pyramid 2.5 meters high.
  4. Painter
    painting_1 How many euros we will pay for repainting the room shaped cuboid with a length of 4.5 meters, width of 2.5 meters and a height of 3 meters, if for 1 m2 with paint we pay € 1.5?
  5. Candies
    bonbon If Alena give Lenka 3 candy will still have 1 more candy. If Lenka give Alena 1 candy Alena will hame twice more than Lenka. How many candies have each of them?
  6. Tiler
    asdasd On what surface m2 tiler must lay 30 square tiles, each of which has a side 25 cm?
  7. Tiles
    tiles_1 The room has dimensions 12 m and 5.6 m. Determine the number of square tiles and their largest possible size to cover them room's floor.
  8. Store
    img-thing Peter paid in store 3 euros more than half the amount that was on arrival to the store. When he leave shop he left 10 euros. How many euros he had upon arrival to the store?
  9. 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?
  10. Tree
    strom How tall is the tree that observed in the visual angle of 52°? If I stand 5 m from the tree and eyes are two meters above the ground.
  11. ISO Triangle V2
    triangle_3 Perimeter of RR triangle (isosceles) is 474 m and the base is 48 m longer than the arms. Calculate the area of this triangle.
  12. Three dice
    3_cubes When you throw three dice was the sum total of the dice 10. The yellow dice fell one eye more than on the red and brown fell 3 eyes less than red. How many eyes fell on every dice?
  13. Snowman
    snehuliak_1 In a circle with a diameter 41 cm are drawn 3 circles /as a snowman/ where: its diameters are integers, each larger circle diameter is 3 cm larger than the diameter of the previous circle. Determine snowman height if we wish highest snowman.
  14. Areaf of ST
    triangle-inside-square It is given square QHFS with side |HF|=18. Calculate area of triangle QSK if vertex K lie on line FH.
  15. Suit
    oblek The suit cost 139 euros. How much cost the pants if it is 60% cheaper than the jacket.
  16. Balls
    kulicky Michal said to Martin: give me one ball and I'll have twice as you. Martin said: give me 9 and we will have equally. How many balls each have?
  17. Count of roots
    eggs How many solutions has equation x. y = 2531 with two unknowns on the set of natural numbers?
  18. Pure quadratic equation
    kvadrat Solve pure quadratic equation ?.
  19. Slope
    slope What is the slope of a line with an inclination 1.06 rad?
  20. Sphere
    1sphere Surface of the sphere is 2260 cm2, weight is 52.2 kg. What is its density?

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