Examples for 9th grade - page 36

  1. Two cars
    car_racing Car A1 goes at average speed of 106 km/h and the second car A2 goes at 103 km/h. How many second will it take car A1 to circulate car A2? Assume that both cars are 5 meters long and the safety gap between cars is 1.5 meters.
  2. Pipeline
    pipeline How much percent has changed (reduced) area of pipe cross-section, if circular shape changed to square with same perimeter?
  3. Train 2
    zssk_vlak The train slowed down from 90 km/h to 72 km/h in 5 seconds. How long track travel?
  4. Ray
    luc-slnka Light ray loses 1/19 of brightness passing through glass plate. What is the brightness of the ray after passing through 7 identical plates?
  5. Cosine
    theta Calculate the cosine of the smallest internal angle in a right-angled triangle with cathetus 3 and 8 and with the hypotenuse 8.544.
  6. Triangular pyramid
    trojboky_ihlan Determine the volume and surface area of a regular triangular pyramid having a base edge a=20 cm and a lateral edge b = 35 cm
  7. Pedestrian and the cyclist
    cyklista_1 Pedestrian and cyclist went against each from the two cities that are distant 40 km. Pedestrian started 30 minutes before the cyclist and walk an average speed of 5 km/h. What speed went cyclist when met after 120 minutes from the start of the pedestrian?
  8. Euclid 5
    euclid_3 Calculate the length of remain sides of a right triangle ABC if a = 7 cm and height vc = 5 cm.
  9. Function
    lin_functions For linear function f(x) = ax + ​​b ‬ is f(14)=179; f(15)=154. Calculate m, if f(m) = 2019 .
  10. Clock hands
    watch_3 The hands on the clock shows the time 12 hours and 2 minutes. Calculate the size of a sharp angle between clock hands three hours later.
  11. Scale
    valec_vykres Cylinder was drawn in scale 2:1. How many times is the volume of the cylinder smaller in reality?
  12. Peleton
    tdf6 Cycling race was run at an average speed of 45 km/h. One cyclist lost with defect 8 minutes. How long and how far he must go at speed 51 km/h to catch peleton again?
  13. Sports games
    kureci_olympiada Pupils of same school participated district sports games. When dividing into teams found that in the case of the creation teams with 4 pupils remaining 1 pupil, in the case of a five-member teams remaining 2 pupils and in the case of six-members teams r
  14. Cable car
    lanovka Cable car rises at an angle 45° and connects the upper and lower station with an altitude difference of 744 m. How long is "endless" tow rope?
  15. Tin with oil
    konzerva Tin with oil has the shape of a rotating cylinder whose height is equal to the diameter of its base. Canned surface is 1884 cm2. Calculate how many liters of oil is in the tin.
  16. Car rent
    car_5 Rental cars are paid a fixed daily fee plus 16 cents for each kilometer traveled. Samuel want to rent a car for a day and worked out that will pay 175 euros. When paying he got a 20% discount on the daily fee, the cost per kilometer is unchanged. Samuel th
  17. Drunk and alcohol
    opilci One drunk measured 2.7 ‰ alcohol in the blood, another 1.75 ‰. How many grams of alcohol in the blood they had if they has 6 kg of blood?
  18. Climb
    aircraft_ascend For horizontal distance 4.9 km road rise by 6.1 m. Calculate the road pitch in ‰ (permille, parts per thousand).
  19. Simple interest
    bank Peter put into bank 790 euros deposit. After 2 years on account overall was 974 euro. What was the interest rate if bank add simple interest?
  20. Rhombus IV
    image005 Calculate the length of the diagonals of the rhombus, whose lengths are in the ratio 1: 2 and a rhombus side is 35 cm.

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