# Examples for 9th grade - page 58

1. Rectangle from string
String 12m. Make rectangle when one side is two times longer than its width.
2. Journey to grandma
Daniel traveled to grandma. He travel 100 km along. Halfway travel by train, one quarter by bus, one tenth by the bicycle and the rest travel by car. How many km travel km by car?
3. The chord
Calculate a chord length which the distance from the center of the circle (S, 6 cm) equals 3 cm.
4. Truncated cone
A truncated cone has a bases radiuses 40 cm and 10 cm and a height of 25 cm. Calculate its surface area and volume.
5. Concrete block
Determine the volume of concrete block whose one edge of the base has a length 3 meters, body diagonal is 13 meters and its height is 12 meters.
6. Driving school
Driving final exam involving 10 attendants. The exam consists of three parts. 2 fails at test (quiz) and 6 students fails on car skills test on playground (slalom between the cone). The practical part of the test - driving in town in the real traffic - al
7. Tram
In the three-part tram went 206 passengers in front of others, 226 after others and in the middle half of all. How many passengers went in tram total?
8. Pupils at cinema
Alena bought movie tickets for two groups of pupils. The first group purchased 7 tickets for 1st and 5 tickets for 2nd place and she pay 62Kč. For the second group bought 11 tickets for 1st and 4 tickets for 2nd place and pay 82Kč. How much was the ticket
9. Surface area 2
Calculate how many % reduce the surface area of the cube is we reduced length of each edge by 10%.
10. Roses
On the large rosary was a third white, half red, yellow quarter and six pink. How many roses was in the rosary?
11. Tent
Pyramid-shaped tent has a base square with a side length of 2 m and a height 1.7 m. How many meters of canvas is nneded to make it if for a waste should be added 10%?
12. Force meter
We put the statuette on the force meter. The force meter showed a value 25 N. Then we placed the statuette on the force meter completely immersed in the water. The force meter showed a value 17 N. What is the volume of the statuette?
13. Acceleration 2
if a car traveling at a velocity of 80 m/s/south accelerated to a velocity of 100 m/s east in 5 seconds, what is the cars acceleration? using Pythagorean theorem
14. Isosceles right triangle
Contents of an isosceles right triangle is 18 dm2. Calculate the length of its base.
15. Chord 2
Point A has distance 13 cm from the center of the circle with radius r = 5 cm. Calculate the length of the chord connecting the points T1 and T2 of contact of tangents led from point A to the circle.
16. Wheel
Diameter of motocycle wheel is 52 cm. How many times rotates wheel on roand long 2 km?
17. Probability - tickets
What is the probability that when you have 25 tickets in 5000 that you wins the first (one) prize?
18. 3 years
The company has increased the number of employees. In year 2005 compared to 2004 13% more, in 2006 18% more against the previous year, in year 2007 20% more compared to 2006. How many % increase in the number of employees in 3 years?
19. Pyramid 4sides
Calculate the volume and the surface of a regular quadrangular pyramid when the edge of the base is 4 cm long and the height of the pyramid is 7 cm.
20. Chord 5
It is given circle k / S; 5 cm /. Its chord MN is 3 cm away from the center of the circle . Calculate its length.

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