Time - examples - page 31

  1. Water lilies
    lekno_2 Water lilies are growing on the pond and their number is doubled every day. The whole layer is covered in 12 days. How many days will it cover 8 layers?
  2. Two ships
    ship_6 The distance from A to B is 300km. At 7 am started from A to B a ferry with speed higher by 20 km/h than a ship that leaves at 8 o'clock from B to A. Both met at 10h 24min. Determine how far they will meet from A and when they reach the destination.
  3. Age
    age_5 In 1960 my age was equal to the digits sum of the year of my birth. What is my age now?
  4. Honza
    calendar_6 Honza is 13 years old and Peter 21 years old. After how many years are their ages will be at ratio 7: 9?
  5. Temperature increase
    teplomer_19 If the temperature at 9:am is 50 degrees. What is the temperature at 5:00pm if the temperature increases 4 degrees Fahrenheit each hour?
  6. A man 2
    penize_49 A man divides $10,000 into two investments, one at 10% and the other at 30%. Find how much is invested at each rate so that the two investments produce the same income annually.
  7. Hour salary
    usd_8 You work for 4 hours on a Saturday and 8 hours on Sunday. You also receive a $50 bonus. You earn $164. How much did you earn per hour?
  8. Constant motion
    car_36 The car has undergone constant motion 120 km in 1 hour 30 minutes. Determine its average speed. Determine how long car drove in the first 20 minutes and 50 minutes from the start of the move.
  9. Free fall
    volny_pad_2_ap The free fall body has gone 10m in the last 0.5s. Find the body speed at the moment of impact.
  10. Gravitation
    vodorovny_vrh From the top of the 80m high tower, the body is thrown horizontally with an initial speed of 15 m/s. At what time and at what distance from the foot of the tower does the body hit the horizontal surface of the Earth? (use g = 10 ms-2)
  11. Car overtaking
    crash_2 A passenger car travels at a speed of 30 m/s, and before it travels freight truck that drives at a constant speed of 10 m/s. Within 30 meters of the truck, the driver of the car finds out that the truck can not overtake. That's why it starts braking with a
  12. Peter and Paul
    clock-night-schr_16 Peter and Paul together have 26 years. Four years ago, Paul was twice older than Peter. How much is Paul and how much Peter?
  13. Bed time
    clock-night-schr_3 Tiffany was 5 years old; her week night bedtime grew by ¼ hour each year. If, at age 18, her curfew time is 11pm, what was her bed time when she was 5 years old?
  14. Train speed
    trains_9 Two guns were fired from the same place at an interval of 10 minutes and 30 seconds, but a person in a train approaching the place hears second shot 10 minutes after the first. The speed of the train (in km/hr), supposing that sound travels at 340 m/s is:
  15. A car
    car_31 A car weighing 1.05 tonnes driving at the maximum allowed speed in the village (50 km/h) hit a solid concrete bulkhead. Calculate height it would have to fall on the concrete surface to make the impact intensity the same as in the first case!
  16. Collision
    motion2_4 The two bodies, whose initial distance is 240 m, move evenly against each other consistently. The first body has an initial velocity of 4 m/s and an acceleration of 3 m/s2, the second body has an initial speed of 6 m/s and an acceleration of 2 m/s2. Find
  17. Minute average
    workers_40 In a factory, four workers are assigned to complete an order received for dispatching 1400 boxes of a particular commodity. Worker A takes 4 mins per box, Worker B takes 6 minutes per box, C takes 10 mins per box, D takes 15 mins per box. Find the average.
  18. Friction coefficient
    car What is the weight of a car when it moves on a horizontal road at a speed of v = 50 km/h at engine power P = 7 kW? The friction coefficient is 0.07
  19. Car crash
    car1_7 On the road, with a maximum permitted speed of 60 km/h, there was a car crash. From the length of the vehicle's braking distance, which was 40 m, the police investigated whether the driver did not exceed that speed. What is the conclusion of the police, as
  20. 40% volume
    workers_41 40% volume with 104 uph (units per labor hour) 8 people working. What is the volume?

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