Percentages - examples - page 12

  1. Energy saving
    energy_star They were released three different, independent inventions saving 12%, 15% and 25% energy. Some considered that while the use of these inventions, the total savings will be 12% + 15% + 25% = 52%. Is this true? How much percent of energy will save all thre
  2. Square - increased perimeter
    rectangles_4 How many times is increased perimeter of the square, where its sides increases by 150%? If the perimeter of square will increase twice, how much% increases the content area of the square?
  3. Copy typist
    pisaci_stroj Typist for 12 hours rewritten 15% of the manuscript. After how many hours he will done 35% of the manuscript?
  4. Washing machine
    washing_masine The price of washing machine was decreased by 21% and then by 55 € due small sales. After two price decreases cost € 343. How much was originally cost?
  5. Salary in enterprise
    1000czk The average salary in the company is 27 000 CZK, 30% of workers have the lowest average income of 19 thousand CZK. There were an increase in the salary in this group by 2%. How much % increased the average salary across the company?
  6. The rod
    pascolour The rod is painted in four colors. 55% of the bar is painted in blue, green 0.2 of rod, 1/8 is brown and the remaining 45 cm of white. How long is rod?
  7. Compound interest
    bank_3 Compound interest: Clara deposited CZK 100,000 in the bank with an annual interest rate of 1.5%. Both money and interest remain deposited in the bank. How many CZK will be in the bank after 3 years?
  8. Bookshelve
    money_15 Bookshelve with an original price of € 200 twice become cheaper. After the second discounted by 15% the price was € 149.60. Determine how much % become cheaper for the first time.
  9. Simple interest 3
    coins-uk_1 Find the simple interest if 11928 USD at 2% for 10 weeks.
  10. Brunette
    brown_eye Of the girls who attend primary school are 30% blondes and 70% brunette. 81% blondes and 19% brunette has blue eyes. How many girls attending school altogether if 470 girls has blue eyes?
  11. The deposit
    money_13 Deposit has been placed for one year at an annual rate of 4.5%. After the added interst amount rose to € 2,612.5. Determine initial deposit.
  12. Millionaire
    money_7 Mr. Smith have gone withdraw from bank saving interest € 1,500. How big was his initial deposit if the annual interest rate is 1.5%?
  13. 3 years savings
    penize_35 Simple interest - Tereza has deposited CZK 100,000 in the bank with an annual interest rate of 1.5%. Interest is added each year and left aside. How many CZK crowns will has total after 3 years?
  14. Uranium ore
    uran Uranium ore contains 0.2% of pure uranium and pure uranium contains 0.07% of fissile uranium. How many grams of fissile uranium contains 2800 ton of uranium ore?
  15. Earth's surface
    earth_globe The greater part of the earth's surface (r = 6371 km) is covered by oceans; their area is approximately 71% of the Earth's surface. What is the approximate area of the land?
  16. Salt
    salt_4 Sea water containing 5% salt. How many kg of fresh water necessary to pour into 40 kg of sea water so that the salinity fell to 2%?
  17. Sugar
    cukr Sugar factory produced 127 tons of sugar in 1 day at 14% sugar content . How many tons of pure beet sugar factory processed in 1 day?
  18. Percentage reduction
    sales_percentages Reducing the unknown number by 19% get number 700.7 Determine unknown number.
  19. Resort
    rekreace In a completely crowded resort was 30% from the Czech Republic quarter visitors were from Slovakia and the rest 135 came from Germany. What capacity have resort?
  20. Human buying irrationality
    athlonxp I longer watch processors for Socket A on ebay, Athlon XP 1.86GHz with a PR rating of 2500+ costs $7 and Athlon XP 2.16Ghz with a PR rating of 3000+ currently cost $16. Calculate: About what percentage of the Athlon XP 2.16Ghz is powerful than Athlon X

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