Examples for 8th grade - page 56

Salt
1 t of sea water contains 25 kg of salt. How many tons of seawater must be evaporated to obtain 2 q of salt?
Triangle
Calculate the area of right triangle ΔABC, if one leg is long 12 and its opposite angle is 31°.
Basketball
Peter and Franta threw to the basket. Each had 20 attempts. Peter scored thirteen and twelve Franta. Give them success in percentage.
Internal and external angles
Calculate the remaining internal and external angles of a triangle, if you know the internal angle γ (gamma) = 34 degrees and one external angle is 78 degrees and 40 '. Determine what kind of triangle it is from the size of its angles.
Fog
The car started in fog at speed 30 km/h. After a 12-minute drive, the fog dissipated and the driver drove next 12 minutes distance 17 km. On the last 17 km long again the driving conditions deteriorated and the driver drove the speed of 51 km/h. a) Calcu
Millionaire
Mr. Smith have gone withdraw from bank saving interest € 1,500. How big was his initial deposit if the annual interest rate is 1.5%?
Classroom
In a class are 26 pupils. Boys are 10 less than girls. How many boys and girls are in the classroom?
Bookshelve
Bookshelve with an original price of € 200 twice become cheaper. After the second discounted by 15% the price was € 149.60. Determine how much % become cheaper for the first time.
Colour - billboard
Shelftalker has the shape of a parallelogram. Its length is 4.9 m and the corresponding height is 3.5 meters. Calculate how much (kg) paint must purchase to redecoration if 1 kg cover 4 m² of shelftalker surface.
Three friends
Peter is eight times older than Rado, Rado is 3 times younger than Joseph. Together they have 120 years. Determine how many are each of them.
Translations
If I going to translate the book 6 pages per day I translate it 4 days earlier than if I translated 5 pages a day. If I translate 4 pages a day I translate it for how many days.....?
Resort
In a completely crowded resort was 30% from the Czech Republic quarter visitors were from Slovakia and the rest 135 came from Germany. What capacity have resort?
3 years
The company has increased the number of employees. In year 1997 compared to 1996 17% more, in 1998 12% more against the previous year, in year 1999 20% more compared to 1998. How many % increase in the number of employees in 3 years?
Cylinder
The cylinder-shaped container has 80 liters of water. The water reaches 45 cm height. How many liters of water will be in a container if water level extend to a height 72 cm? Write the result in liters, write down only as a whole or decimal number.
Park
In the park is marked diamond shaped line connecting locations A, D, S, C, B, A. Calculate its length if |AB| = 108 m, |AC| = 172.8 m.
Giant coin
From coinage metal was produced giant coin and was applied so much metal, such as production of 10 million actual coins. What has this giant coin diameter and thickness, if the ratio of diameter to thickness is the same as a real coin, which has a diameter
Star
Calculate the content of the shaded part of square with side 43 cm.
Painting school
Redecoration school had scheduled for four crew to 10 days. After two days a single worker ill. For how many days the school was painted when remain workers working with the same tempo?
Goods
To the market is introducing a new product, the first week is sold at a reduced price. 5 products is sell at an entry price same as 3 products at the normal price. How much % is reduced price less than the current price for this product?
Triangle eq
Calculate accurate to hundredths cm height of an equilateral triangle with a side length 12 cm. Calculate also its perimeter and content area.

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