Inverse relationship - examples

  1. Thunderstorm
    storm-012_1 The sound travels 1 km in about 3 seconds. How far is the storm if there is a time interval of 8 seconds between lightning and thunder?
  2. Trapezoid - intersection of diagonals
    intersect_trapezoid_diagonals In the ABCD trapezoid is AB = 8 cm long, trapezium height 6 cm, and distance of diagonals intersection from AB is 4 cm. Calculate trapezoid area.
  3. Five pumps
    nadrz_14 The water tank is filled with two pumps in 48 minutes. How long would it take to fill it with 5 same pumps?
  4. Pool
    pool If water flows into the pool by two inlets, fill the whole for 18 hours. First inlet filled pool 10 hour longer than second. How long pool is filled with two inlets separately?
  5. Chocolate
    cokolada Ivan bought 7 same chocolates for 28 Eur. How many euros he pay for 21 chocolates?
  6. Forestry workers
    forestry_workers In the forest is employed 64 laborers planting trees in nurseries. For 8 hour work day would end job in 35 days. After 12 days, 20 laborers go forth. How many days is needed to complete a planting trees in nurseries by others, if they will work 9 hours a
  7. Excavation
    vykop_ryha 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?
  8. 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
  9. Chickens
    chickens 2 chickens give 2 eggs in 2 days. How many eggs can give 8 chickens for 8 days?
  10. Washer
    pracka Washing machine drum wash at 54 RPM. Washing machine motor pulley has diameter 5 cm. What must be the diameter of the drum machine pulley when the motor is at 301 RPM?
  11. ŽSR
    luzianky Calculate fixed annual personnel costs of operating monorail line 118 km long if every 5 km is station, which serve three people - one dispatcher and two switchman in 4-shift operation. Consider the average salary of the employee 885 €.
  12. Pipes
    water_pipe Water pipe has a cross-section 1405 cm2. An hour has passed 756 m3 of water. How much water flows through the pipe with cross-section 300 cm2 per 15 hours if water flow same speed?
  13. Cats
    cats Two cats caught two mice in two days. How many mouses will catch 6 cats for 6 days?
  14. Tractors
    tractors Fields go plow two tractors with various performance. The first tractor plow whole field in 11 hours, the second tractor plow whole field 39 hours longer. How long take plow whole field with two tractors?
  15. Cyclist
    1cyclist Cyclist goes uphill 10 km for 50 minutes and downhill minutes for 29 minutes, both applied to the pedals same force. How long he pass 10 km by plane?
  16. Wage
    socik Increasing the minimum wage while maintaining the other parameters of the system, unemployment will be:
  17. Engineer Kažimír
    demagog_smer_1 The difference between politicians-demagogues and reasonable person with at least primary education beautifully illustrated by the TV show example. "Engineer" Kažimír says that during their tenure there was a large decline in the price of natural gas, pri
  18. Road repair
    workers_1 Road repair took 10 days for 36 workers if they worked 9 hours a day. How many days take repair same road 37 workers if they work 8 per day?
  19. Tare
    camion Gross weight of shipment is 5188 kg and its tare is 5.6%. Calculate the net weight of the shipment.
  20. Car
    american-cars Car goes from point A to point B at speed 86 km/h and back 53 km/h. If they goes there and back at speed 67 km/h trip would take 10 minutes shorter. What is distance between points A and B?

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