Unit conversion - 9th grade (14y) - examples

  1. Acres
    plocha_1 Two hours 24 students harvested chestnuts on 36 acres. How many square meters harvested one student per hour?
  2. Mirror
    mirror How far must Paul place a mirror to see the top of the tower 12 m high? The height of Paul's eyes above the horizontal plane is 160 cm and Paul is from the tower distant 20 m.
  3. Beer
    piva After three 10° beers consumed in a short time there are 7.4 g of alcohol in 5 kg adult human blood. How much is it per mille?
  4. Pool
    swimming-pool The swimming pool is 6 m wide and 14 m long and 185 cm deep. How many hectoliters of water is in it, if the water is 9 cm below its upper edge.
  5. 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.
  6. Clock
    hodiny How many times a day hands on a clock overlap?
  7. Mountain railway
    semmering Height difference between points A, B of railway line is 38.5 meters, their horizontal distance is 3.5 km. Determine average climb in permille up the track.
  8. Server
    p_pro Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%.
  9. Compass
    wind_rose What angle are between directions W (West) and SE (SouthEast) on the compass?
  10. Beer permille
    pivo In the 5 kg of blood of adult human after three 10° beers consumed shortly after another is 6.6 g of the alcohol. How much is it as per mille?
  11. Cube and water
    krychle_3 How many liters of water can fit into a cube with an edge length of 0.11 m?
  12. Water tank 2
    tank_1 Water tank cuboid is 12 meters long and 6.5 meters wide and 1.2 meters high. How many hectoliters are in the tank when it is filled to 71%?
  13. Water
    storm_1 On the lawn which has area 243 m2 rained 5 mm of water. How many liters of water rained?
  14. Water inlets
    pipe Inlet valve with a flow rate of 12 liters per second is filled tank for 72 minutes. How long take to fill full tank if we open one more such valve half an hour after?
  15. Water tank
    akvarium_1 Water tank shape cuboid has a width of 3.3 m and length twice larger. How high will reach water if water flow into 15 liters of water per second during 23 minutes?
  16. Scale
    pool_1 Swimming pool is long 110 m and 30 m wide. The plan of the city is shown as a rectangle with area 13200 cm2. What scale is the city plan?
  17. 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
  18. Tank and water
    chemickelaboratorium1 Cylindrical tank were poured with 3.5 liters of water. If tank base diameter is 3 dm, how height is water level in?
  19. Pumps
    number-1 First pump flows 16 liters per second into the basin by the second pump 75% of the first and by third pump half more than the second. How long will take fill basin by all three pumps simultaneously volume 15 m3 (cubic meters)?
  20. Water level
    hladina.JPG How high reaches the water in the cylindrical barell with a diameter of 12 cm if there is a liter of water? Express in cm with an accuracy of 1 decimal place.

Do you have interesting mathematical example that you can't solve it? Enter it and we can try to solve it.

To this e-mail address we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.