Examples for 8th grade - page 72

  1. Paper box
    cuboid_5 Calculate the consumption of paper on the box-shaped quadrangular prism with rhombic footstall, base edge a=6 cm and the adjacent base edges forms an angle alpha = 60 °. Box height is 10 cm. How many m2 of the paper consumed 100 such boxes?
  2. 3 days
    kontrolor Worker checked 2,950 products in 3 days. Second day checked 25% more than the first day. The third day 15% more products than the second day. How many products he checked in each day.
  3. Trapezoid RT
    lichobeznik2 The plot has a shape of a rectangular trapezium ABCD, where ABIICD with a right angle at the vertex B. side AB has a length 36 m. The lengths of the sides AB and BC are in the ratio 12:7. Lengths of the sides AB and CD are a ratio 3:2. Calculate consumptio
  4. Round table tablecloth
    obrus Round table has area 50.24 dm2. Calculate the diameter of the circular tablecloth, if it is extend beyond the edge of the table by 30 cm.
  5. Antennas
    antenas If you give me two antennas will be same. If you give me again your two antenna I have a 5× so many than you. How many antennas have both mans?
  6. Clocks
    clocks How long track travel the second hand in 44 hours, the end of which is 4 cm long.
  7. Bank deposit
    bank_1 Ms Jana after the withdraw amount of 2,500 euros after year saving in bank. What was her deposit if the interest rate was 2.5% p.a..
  8. Holidays
    ndr Of the 35 students of class were 7 on holiday in Germany and just as much in Italy. 5 students visited Austria. In none of these countries was 21 students, all three visited by one student . In Italy and Austria were 2 students and in Austria and Germany.
  9. Calcium and citality
    milk_products The daily dose of calcium obtained using 0.75 liters of milk and 60 grams of cheese. A/ At the morning I drank half a liter of milk. How much cheese I must eatto eat a daily dose of calcium? b / I ate 50 grams of cheese, how much milk I must drink? c /.
  10. Garden pool
    basen_1 Mr. Novak fill garden pool (cylinder; diameter of 200 cm) with 31.4 hl of water. What is the depth of the pool when the water level is 10 cm below the upper edge of the pool?
  11. Medians in triangle
    stredne_pricky Median of isosceles triangle has a length 3 cm. Determine the length of its sides if its perimeter is 16 cm.
  12. Mrs XY
    crime Mrs Novak is employed. In January 2015 the gross income reached € 1193. Insurance is a 286.32 euros, and income taz 136 euros. Employer precipitated Mrs. Novak in recent clashes € 142, of which 64 euro for the savings account, and 78 euros for repayment of
  13. Iron sphere
    sphere_1 Iron sphere has weight 100 kg and density ρ = 7600 kg/m3. Calculate the volume, surface and diameter of the sphere.
  14. The carpet
    koberec_1 How many meters of carpet 90 cm wide need to cover floor room which has a rectangular shape with a lengths 4.8 m and 2.4 m if the number of pieces on the carpet is needed to be lowest?
  15. Pit
    ihlan_zrezany Pit has shape of a truncated pyramid with rectangular bases and is 2.8 m deep. The length and width of the pit is the top 3 × 1.5 m bottom 1 m × 0.5 m. To paint one square meter of pit we use 0.3 l of green colour. How many liters of paint is needed when w
  16. Medal
    gold_medail Calculate the approximate weight of the gold Olympics medal, if its diameter is 9 cm and a thickness 6 mm. The density of gold find out in the tables or on the Internet.
  17. Aircraft
    aircraft_soviet The aircraft has in a fuel tank 100 hl of aviation fuel and flight consumes 4.3 liters of fuel. Identify the function, which expresses the dependence of the volume of fuel in tank on the track distance plane flew by. How many hectolites of fuel is still i
  18. Playground
    plot_ihrisko.JPG Fencing square playground cost € 303; 1 meter cost € 15. What is the area of the playground?
  19. Saw
    bosh_saw Blade circular saw with a diameter 42 cm turns 825 times per minute. Expresses his cutting speed in meters per minute.
  20. Password
    codes The voltage station is every day changing the master password, which consists of three letters. Code generation process does not change and is based on the following procedure: The following letters (A) to (I) correspond to different numbers from 1 to 9. I

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