# Examples for 9th grade - page 35

1. Sphere fall How many percent fall volume of sphere if diameter fall 10×?
2. Railways - golden parachutes As often happens in Slovakia habit, the state's financial institution which takes from poverty and gorilas give. A hardworking punishing taxes. Let's look at a short work of director Railway Company ZSSK - Mgr . P. K. : 18 months 'work' as director .
3. Train 2 The train slowed down from 90 km/h to 72 km/h in 5 seconds. How long track travel?
4. Triangular pyramid 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
5. The camp At the end of the camp a 8 friends exchanged addresses. Any friend gave remaining 7 friends his card. How many addresses they exchanged?
6. Pipeline How much percent has changed (reduced) area of pipe cross-section, if circular shape changed to square with same perimeter?
7. Trigonometry Is true equality? ?
8. Two cars 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.
9. Ray Light ray loses 1/19 of brightness passing through glass plate. What is the brightness of the ray after passing through 7 identical plates?
10. Clock hands 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. Euclid 5 Calculate the length of remain sides of a right triangle ABC if a = 7 cm and height vc = 5 cm.
12. Cosine Calculate the cosine of the smallest internal angle in a right-angled triangle with cathetus 3 and 8 and with the hypotenuse 8.544.
13. Pedestrian and the cyclist 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?
14. Function For linear function f(x) = ax + ​​b ‬ is f(14)=179; f(15)=154. Calculate m, if f(m) = 2019 .
15. Drunk and alcohol 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?
16. Annulus Two concentric circles form an annulus of width 10 cm. The radius of the smaller circle is 20 cm. Calculate the content area of annulus.
17. Scale Cylinder was drawn in scale 2:1. How many times is the volume of the cylinder smaller in reality?
18. Climb For horizontal distance 4.2 km road rise by 6.3 m. Calculate the road pitch in ‰ (permille, parts per thousand).
19. Simple interest 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. Peleton 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?

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