Examples for 9th grade - page 9

  1. Words
    words How many 3 letter "words" are possible using 18 letters of the alphabet? a) n - without repetition b) m - with repetition
  2. Triangle ABC
    ABC Right triangle ABC with right angle at the C, |BC|=20, |AB|=35. Calculate the height of the triangle hAB to the side AB.
  3. MATES
    sazka In MATES (Small Television tipping) from 35 randomly numbers drawn 5 winning numbers. How many possible combinations there is?
  4. Scrap
    chair_bad From 8 products are 2 scrap. What is the probability that the random pick of 2 products have no defective product?
  5. Pipes
    water_pipe Water pipe has a cross-section 1939 cm2. An hour has passed 567 m3 of water. How much water flows through the pipe with cross-section 300 cm2 per 14 hours if water flow same speed?
  6. 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.
  7. 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.
  8. 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
  9. Subsets
    1venna_sets How many is subsets of set ??
  10. 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?
  11. Three digits number
    plot How many are three-digit integers such that in they no digit repeats?
  12. Lines
    lines_1 In how many points will intersect 11 different lines, where no two are parallel?
  13. Dice
    dices How many times must throw the dice, the probability of throwing at least one three was greater than 90%?
  14. 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?
  15. 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?
  16. 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.
  17. Welders
    svarec Welder do the job for six hours, the second one for 8 hours. How long do the job third welder if all together can do job in 2 hours?
  18. Root
    sq_root Use law of square roots roots: ?
  19. 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.
  20. Combinations
    circles.GIF How many different combinations of two-digit number divisible by 4 arises from the digits 3, 5 and 7?

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