Excavation

Mr. Billy calculated that excavation for a water connection dig for 12 days. His friend would take 10 days. Billy worked 3 days alone. Then his friend came to help and started on the other end.

On what day since the beginning of excavation they met?

Result

n =  8

Solution:

Solution in text n =

3 / 12 +(n-3)/12 + (n-3)/10 = 1

11n = 78

n = 7811 ≈ 7.090909

Calculated by our simple equation calculator.







Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...):

Showing 0 comments:
1st comment
Be the first to comment!
avatar




Do you have a linear equation or system of equations and looking for its solution? Or do you have quadratic equation?

Next similar examples:

  1. Diophantus
    diofantos_1 We know little about this Greek mathematician from Alexandria, except that he lived around 3rd century A.D. Thanks to an admirer of his, who described his life by means of an algebraic riddle, we know at least something about his life. Diophantus's youth l
  2. River
    kongo_river Calculate how many promiles river Dunaj average falls, if on section long 957 km flowing water from 1454 m AMSL to 101 m AMSL.
  3. Logic
    blue-barrel A man can drink a barrel of water for 26 days, woman for 48 days. How many days will a barrel last between them?
  4. Sea water
    sea Mixing 34 kg of sea water with 34 kg rainwater is created water containing 3.4% salt. How many percent sea water contains salt?
  5. Acid
    acid_1 The barrel is 199 litres of 38% acid. How many percent acid occurs when 61 litres revoke and replace it with the same amount of water?
  6. Peroxide
    peroxide_h How much distilled water (in liters) must pharmacists pour into 300 ml of 23.6% solution of hydrogen peroxide to get 2.7% solution to gargle?
  7. Store
    pave One meter of the textile were discounted by 2 USD. Now 9 m of textile cost as before 8 m. Calculate the old and new price of 1 m of the textile.
  8. Coffee
    coffe In stock are three kinds of branded coffee prices: I. kind......248 Kč/kg II. kind......134 Kč/kg III. kind.....270 Kč/kg Mixing these three species in the ratio 10:7:7 create a mixture. What will be the price of 1100 grams of this mixture?
  9. Alcohol
    no_alcohol How many 55% alcohol we need to pour into 14 liters 75% alcohol to get p3% of the alcohol? How many 65% alcohol we get?
  10. Bonus
    moeny Gross wage was 527 EUR including 16% bonus. How many EUR were bonuses?
  11. Troops
    regiment Route is long 147 km and the first day first regiment went at an average speed 12 km/h and journey back 21 km/h. The second day went second regiment same route at an average speed 22 km/h there and back. Which regiment will take route longer?
  12. Motion problem
    dragway From Levíc to Košíc go car at speed 81 km/h. From Košíc to Levíc go another car at speed 69 km/h. How many minutes before the meeting will be cars 27 km away?
  13. Beer
    piva After three 10° beers consumed in a short time there are 5.6 g of alcohol in 6 kg adult human blood. How much is it per mille?
  14. Motion
    cyclist_1 If you go at speed 3.7 km/h, you come to the station 42 minutes after leaving train. If you go by bike to the station at speed 27 km/h, you come to the station 56 minutes before its departure. How far is the train station?
  15. Medicament
    tablets Same type of medicament produces a number of manufacturers in a variety of packages with different content of active substance. Pack 1: includes 60 pills of 600 mg of active substance per pack cost 9 Eur. Pack 2: includes 150 pills of 500 mg of active sub
  16. Hands
    soviet_watch The clock shows 12 hours. After how many minutes will agle between hour and minute hand 90°? Consider the continuous movement of both hands hours.
  17. Rectangular cuboid
    cuboid_1 The rectangular cuboid has a surface area 5334 cm2, its dimensions are in the ratio 2:4:5. Find the volume of this rectangular cuboid.