Examples for 9th grade - page 9

  1. 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
  2. Three digits number
    plot How many are three-digit integers such that in they no digit repeats?
  3. Machine
    machine Price of the new machine is € 56000. Every year is depreciated 16% of residual value. What will be the value of the machine after 5 years?
  4. Dice
    dices How many times must throw the dice, the probability of throwing at least one three was greater than 90%?
  5. Lines
    lines_1 In how many points will intersect 11 different lines, where no two are parallel?
  6. 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.
  7. 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?
  8. Barrel of oil
    dieselbarrel Barrel of oil weighs 282 kg. When it mold 56% oil, weighed 138 kg. What is the mass of the empty barrel?
  9. Root
    sq_root Use law of square roots roots: ?
  10. 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?
  11. Morse alphabet
    morse_code Calculate how many words of Morse code to create compiling commas and dots in the words of one to five characters.
  12. Store
    pave One meter of the textile were discounted by 2.4 USD. Now 6 m of textile cost as before 3 m. Calculate the old and new price of 1 m of the textile.
  13. Combinations
    circles.GIF How many different combinations of two-digit number divisible by 4 arises from the digits 3, 5 and 7?
  14. Server
    p_pro Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%.
  15. Salary
    500euro Clerk got to pay 1200 Euros in banknotes of 50 and 200 Eur. Total got 9 banknotes. How many was which?
  16. Road - permille
    18procent 5 km long road begins at an altitude 500 meters above sea level and ends at a altitude 521 ASL. How many permille road rises?
  17. Tanker
    oil-tanker An oil tanker can be emptied by the first pump in 4.4 hours. Second pump can empty an tanker in 7.8 hours. If the first pump started at 8:00 and second 1.4 hour later, at what time will the tanker be empty?
  18. Party
    party-informatikov At party overyone clink with everyone. Together, they clink 406 times. How many people were at the party?
  19. 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
  20. Circles
    three-circles Three circles of radius 71 cm 76 cm and 22 cm is mutually tangent. What is the perimeter of the triangle whose vertices are centers of the circles?

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