# Examples for 8th grade - page 62

1. Percentages Expressed as a percentage:
2. 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.
3. 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
4. New refrigerator New refrigerator sells for 1024 USD, Monday will be 25% discount. How much USD will save, and what will be the price?
5. 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?
6. 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
7. Proof I When added to the product of two consecutive integers larger one, we get square larger one. Is this true or not?
8. Roses On the large rosary was a third white, half red, yellow quarter and six pink. How many roses was in the rosary?
9. Surface area 2 Calculate how many % reduce the surface area of the cube is we reduced length of each edge by 10%.
10. Goods To the market is introducing a new product, the first week is sold at a reduced price. 8 products is sell at an entry price same as 5 products at the normal price. How much % is reduced price less than the current price for this product?
11. 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?
12. Isosceles right triangle Contents of an isosceles right triangle is 18 dm2. Calculate the length of its base.
13. 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.
14. Wheel Diameter of motocycle wheel is 52 cm. How many times rotates wheel on roand long 2 km?
15. 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?
16. Tripled square If you tripled the length of the sides of the square ABCD you increases its content by 200 cm2. How long is the side of the square ABCD?
17. Probability - tickets What is the probability when you have 25 tickets in 5000 that you not wins the first (one) prize?
18. Runners circle Pepa circles the track in 36 seconds. Kamil in 42 seconds. They started together. How many seconds will meet again at the start?
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. Ethnicity Share of ethnicity XY is 26%, which is 1/9 more than in the prewar period. What was the share of that ethnicity in the pre-war period?

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