Examples for 8th grade - page 12

  1. Three friends
    Veverka Three friends squirrels together went to collect hazelnuts. Zrzecka he found more than twice Pizizubka and Ouska even three times more than Pizizubka. On the way home they talked while eating and was cracking her nuts. Pizizubka eaten half of all nuts whi
  2. Tablecloth
    decka I embroider tablecloth in 20 days, if I embroider 3/4 hours a day; I have embroider it for 15 days. How long do I embroider a day?
  3. Wire
    cu_wire One pull of wire is reduced its diameter by 9%. What will be diameter of wire with diameter 9 mm over 8 pulls?
  4. Cosine
    cosine The point (21, 20) is on the terminal side of angle θ. cos θ = ?
  5. Sugar - cuboid
    kocky_cukor Pejko received from his master cuboid composed of identical sugar cubes with count between 1000 and 2000. The Pejko eat sugar cubes in layers. The first day eat one layer from the front, second day one layer from right, the third day one layer above. Yet i
  6. Cable car 2
    lanovka_1 Cable car rises at an angle 39° and connects the upper and lower station with an altitude difference of 345 m. How long is the track of cable car?
  7. Semicircle
    tales-de-mileto In the semicircle with center S and the diameter AB is constructed equilateral triangle SBC. What is the magnitude of the angle ∠SAC?
  8. OPT
    right_triangle_pythagoras What is the perimerer of a right triangle with the cathetuses 20 cm and 13 cm?
  9. Cars plates
    car_plate How many different licence plates can country have, given that they use 3 letters followed by 4 digits?
  10. Pillar
    sliced_pyramid Calculate volume of pillar shape of a regular tetrahedral truncated pyramid, if his square have sides a = 17, b = 22 and height is v = 36.
  11. Radians
    pi_text Convert 54° to radians. Write result as multiple of number π.
  12. Two diggers
    two-diggers There are two diggers. One digger digs a pit 83 hours second gidding 1.4 times faster. a) how long took to dig a pit second digger b) how long took dig together
  13. Rhombus ABCD
    rhombus6 Rhombus ABCD, |AC| = 42 cm, |BD| = 96 cm. Calculate the perimeter of the rhombus ABCD.
  14. BW-BS balls
    balls_3 Adam has a full box of balls that are large or small, black or white. Ratio of large and small balls is 5:3. Within the large balls the ratio of the black to white is 1:2 and between small balls the ratio of the black to white is 1:8 What is the ratio of.
  15. Double percent
    percents What is 70% of 70% of 10500?
  16. Acid
    acid_1 The barrel is 239 litres of 31% acid. How many percent acid occurs when 88 litres revoke and replace it with the same amount of water?
  17. Farmer
    krava The farmer farming 332 ha of arable land and the remaining 11% are meadows and pastures. How much land farmer owns?
  18. 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.
  19. Swimming pool 4
    bazen_1 The pool shaped cuboid measuring 12.5 m × 640 cm at the bottom is 960hl water. To what height in meters reaches the water level?
  20. Mortgage
    hypo_real_estate Family XY wants to take the bank mortgage (loan for an apartment/house) in the amount of € 100,000. Bank for processing the mortgage charges a fee of 0.79% of the amount borrowed. How many euros is this fee?

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