Examples for 8th grade - page 9

  1. Rhombus HP
    rhombus3_1 Calculate area of the rhombus with height 98 mm and perimeter 20 mm.
  2. Meadow
    ovce-miestami-baran On the meadow grazing horses, cows and sheep, together less than 200. If cows were 45 times more, horses 60 times more and sheep 35 times more than there are now, their numbers would equall. How many horses, cows and sheep are on the meadow together?
  3. Daily average
    weather_forecast Calculate the average temperature during the day, when 14 hours was 20 °C and 10 hours was 15 °C.
  4. Inflation
    tsar Once upon a time, tsar owned a money printer and printed and printed. The result of printing money prices went up,in the first year 5.9 %, in the second 2.4%, in the third 5.9% and in the fourth 5.7%. Then tsar was failed in election. Calculate the av
  5. Lines
    bus Five bus lines runs at intervals 3, 5, 10, 11, 13 minutes. In the morning, suddenly start at 7:00. After how many minutes the bus lines meet again?
  6. Words
    words How many 3 letter "words" are possible using 18 letters of the alphabet? a) n - without repetition b) m - with repetition
  7. MATES
    sazka In MATES (Small Television tipping) from 35 randomly numbers drawn 5 winning numbers. How many possible combinations there is?
  8. Proof I
    ithinkiam When added to the product of two consecutive integers larger one, we get square larger one. Is this true or not?
  9. Scrap
    chair_bad From 8 products are 2 scrap. What is the probability that the random pick of 2 products have no defective product?
  10. Painters
    natieraci Five painters painting the fence for eight days. How many days over will take work if paint the fence only four decorators?
  11. 3y inflation
    bread Price of the bread rise in the first year by 7%, the second year fell by 4% and in the third year increased by 8%. Calculate the average annual increase in price of the bread.
  12. No. of divisors
    triangle_div How many different divisors has number ??
  13. Basketball
    friends_1 Peter and Franta threw to the basket. Each had 20 attempts. Peter scored thirteen and twelve Franta. Give them success in percentage.
  14. Two typists
    lasica_typewriter There are two typists who are rewriting the material 705 pages. First can it handle rewrite yourself for 24 days; the second 12 days. First typist wrote material yourself 4 days rest rewrites yourself second typist. How many days will it take rewriting alt
  15. 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.
  16. Three digits number
    plot How many are three-digit integers such that in they no digit repeats?
  17. Divisors
    divisors The sum of all divisors unknown odd number is 1482. Determine sum of all divisors of number which is twice of unknown numbers.
  18. Parquet floor
    Parkett Three workers laid parquet floor for 1.957 hour. The first one would do this work alone 5 hours, the second in 9 hours. For how many hours would fulfill this work the third worker, if he worked alone?
  19. Lock
    combination-lock Combination lock will open when the right choice of 5 numbers (from 1 to 12 inclusive) is selected. A. How many different lock combinations are possible? B. Is he combination lock named appropriately?
  20. Height 2
    1unilateral_triangle Calculate the height of the equilateral triangle with side 43.

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