Percentages - 9th grade (14y) - examples

Our percentage calculator will help you quickly calculate various typical tasks with percentages.

  1. Repay, interest, loan
    repay Ramchacha takes a loan amount of 240000 from a bank for constructing a house at the rate of simple interest of 12% per annum. After 1 yr. of taking the loan he rents the house at the rate of 5200 per month. Determine the number of years he would take to re
  2. Volume and body diagonal
    kvader11_11 Calculate how much the volume and body diagonal of the cuboid decrease if we reduce each of its three edges a, b, c by 18%?
  3. Profit gain
    percent_12 If 5% more is gained by selling an article for Rs. 350 than by selling it for Rs. 340, the cost of the article is:
  4. Ebay is not free
    usd_7 Be aware of ebay - if you sell something expensive, fee is painful. There are lot of space for classifieds and local exchange away from global ebay. Calculate ebay+paypal fee if you sale 3641 USD laptop. Formula for ebay fee is 0,30 + 10 % of total earning
  5. Red balls
    gule_3 In the bag there are 3 red, 12 blue and 8 green balls. How many red balls we must be attached to the bag if we want the probability of pulling out the red balls was 20%?
  6. Competitors
    ski_2 In the first round of slalom fell 15% of all competitors and in the second round another 10 racers. Together, 40% of all competitors fell. What was the total number of competitors?
  7. Bonus
    moeny Gross wage was 1762 USD including 22% bonus. How many USD were bonuses?
  8. River
    kongo_river Calculate how many promiles river Hudson average falls, if on section long 921 km flowing water from 1224 m AMSL to 154 m AMSL.
  9. Server
    p_pro Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%.
  10. Rectangle
    diagonal In rectangle with sides 10 and 9 mark the diagonal. What is the probability that a randomly selected point within the rectangle is closer to the diagonal than to any side of the rectangle?
  11. Tanks
    hasici Fire tank has cuboid shape with a rectangular floor measuring 11 m × 14.3 m. Water depth is 1.3 m. Water was pumped from the tank into barrels with a capacity of 3.9 hl. How many barrels were used, if the water level in the tank fallen 3 cm? Wri
  12. Vinegar 2
    ocet How many percentage of getvinegar solution, if we mix to 14.5 liters of 7.8% and 2.5 liters of 5.8% vinegar?
  13. Ace
    ace From complete sets of playing cards (32 cards) we pulled out one card. What is the probability of pulling the ace?
  14. Gutter
    okap How much metal is needed for production 37 pieces of gutter pipes with the diameter 16 cm and length of 1 m? The plate bends add 7% of the material.
  15. Sea water
    sea_1 Seawater contains about 7% salt. How many dm3 of distilled water we must pour into 14 dm3 of sea water to get water with 1.7% salt?
  16. Barrel of oil
    dieselbarrel Barrel of oil weighs 238 kg. When it mold 20% oil, weighed 196 kg. What is the mass of the empty barrel?
  17. Lathe
    soustruh From the cube of edge 52 cm was lathed maximum cylinder. What percentage of the cube is left as waste after lathed?
  18. Cube zoom
    krychle_1 How many percent we increase volume and surface of cube, if we magnify its edge by 61%.
  19. VAT
    Tax John paid 1000 Euros in store for purchase. Calculate value added tax (VAT), which paid in purchase, if the VAT rate is 20%.
  20. Tower
    HexagonalPyramid_4 The top of the tower is a regular hexagonal pyramid with base edge 9.2 meters long and a height 9.6 meters. How many m2 of sheet is required to cover the top of the tower if we count 12% of the sheet waste?

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