Units - examples

  1. Clock's gears
    orloj In the clock machine, three gears fit together. The largest has 168 teeth, the middle 90 teeth, and the smallest 48 teeth. The middle wheel turns around its axis in 90 seconds. How many times during the day do all the gears meet in the starting position?
  2. Find the 6
    pc_smile_1 Find the total cost of 10 computers at $ 2100 each and 7 boxes of diskettes at $12 each
  3. Two diggers
    digging Two diggers should dig a ditch. If each of them worked just one-third of the time that the other digger needs, they'd dig up a 13/18 ditch together. Find the ratio of the performance of this two diggers.
  4. Temperature 5
    teplomer_14 Temperature outside starts at 0 Fahrenheit. Over time the temperature changes at a rate of -0.6 Fahrenheit per hour. How long will it take for the temperature to reach -4.5 Fahrenheit?
  5. Spherical tank
    spherical-tanks The tank of a water tower is a sphere of radius 35ft. If the tank is filled to one quarter of full, what is the height of the water?
  6. Overtaking
    dopravni-znacka-zakaz-predjizdeni On the direct road, the passenger car overtakes the slower bus by starting to overtake 20 meters from the bus and after passing it ahead of it again 20 meters away. The car overtakes at a steady speed of 72 km/h, the bus goes at a steady speed of 54 km/h..
  7. The swimmer
    river_3 The swimmer swims at a constant speed of 0.85 m/s relative to water flow. The current speed in the river is 0.40 m/s, the river width is 90 m. a) What is the resulting speed of the swimmer with respect to the tree on the riverbank when the swimmer motion
  8. Paratrooper
    padak After the parachute is opened, the paratrooper drops to the ground at a constant speed of 2 m/s, with the sidewinding at a steady speed of 1.5 m/s. Find: a) the magnitude of its resulting velocity with respect to the ground, b) the distance of his land fr
  9. Tickets 4
    cinema2_13 Stacey is selling tickets to the school play. The tickets are $7 for adults and $5 for children. She sells twice as many adult tickets as children's tickets and brings in a total of $342. How many of each kind of ticket did she sell?
  10. Outside temperature
    teplomer_13 The temperature outside was 57 degree Fahrenheit. During the next few hours it decreased by 18 degrees and then increased by 23 degrees. Find new temperature.
  11. Supplementary angles
    susedne_huly One of the supplementary angles is larger by 33° than the second one. Calculate the angles size.
  12. Edges or sides
    cube_shield_4 Calculate the cube volume, if the sum of the lengths of all sides is 276 cm.
  13. The position
    motion2_3 The position of a body at any time T is given by the displacement function S=t3-2t2-4t-8. Find its acceleration at each instant time when the velocity is zero.
  14. Discount
    saty_1 The dress was discounted by CZK 115, which was 12% of the original price. What is the cost of the dress after the discount?
  15. In what
    vaha2 In what ratio must two sorts of sugar, costing #390 and #315 per kg respectively, be mixed in order to produce a mixture worth #369 per kg?
  16. Ping time
    fibre Calculate theoretical ping time between Orlando and Shenzhen which is 14102 km distant. Ping time measures the round-trip time for small messages sent from the origin to a destination that is echoed back to the source. The name comes from active sonar term
  17. Phone plan
    phones_3 Victoria's cell phone plan costs $30.00 a month. If she used 12.5 hours in May, how much did Victoria pay per minute?
  18. Body diagonal
    krychle_12 Calculate the volume and surface of the cube if the body diagonal measures 10 dm.
  19. Water level
    bazen_11 How high is the water in the swimming pool with dimensions of 37m in length and 15m in width, if an inlet valve is opened for 10 hours flowing 12 liters of water per second?
  20. Workers 9
    okno2_2 If two workers fix two windows in an hour how many windows can 18 workers fix in the same two windows?

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