Examples for 8th grade - page 8

  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. 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.
  4. 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?
  5. Forestry workers
    forestry_workers In the forest is employed 63 laborers planting trees in nurseries. For 11 hour work day would end job in 43 days. After 14 days, 22 laborers go forth. How many days is needed to complete a planting trees in nurseries by others, if they will work 15 hours
  6. Height 2
    1unilateral_triangle Calculate the height of the equilateral triangle with side 43.
  7. 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?
  8. Root
    sq_root Use law of square roots roots: ?
  9. Mine
    minetower Wheel in traction tower has a diameter 5 m. How many meters will perform an elevator cabin if wheel rotates in the same direction 10 times?
  10. 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.
  11. Plumber
    klempir Plumber had to cut the metal strip with dimensions 380 cm and 60 cm to the largest squares so that no waste. Calculate the length of the sides of a square. How many squares cut it?
  12. Arithmetic average
    ap The arithmetic mean of the five numbers is exactly 8. The sum of these four numbers is 30. What is the fifth number?
  13. Tare
    camion Gross weight of shipment is 5073 kg and its tare is 6.9%. Calculate the net weight of the shipment.
  14. Hiker
    hiker Hiker went half of trip the first day, the third of trip the second day and remaines 13 km. How long trip he planned?
  15. Ratio
    ratio_2 Unfold number 4712 in the ratio 10:14:7.
  16. Salary
    500euro Clerk got to pay 1200 Euros in banknotes of 50 and 200 Eur. Total got 9 banknotes. How many was which?
  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. Server
    p_pro Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%.
  19. Water
    tanks Mix 61 l of water with temperature of 48 °C, 58 l warm of 57 °C and 47 l water of 39 °C. What is the temperature of the mixed water immediately after mixing?
  20. 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

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