Examples for 8th grade - page 59

Copiers
Three copiers will do the same in an hour k copies. How many copies would be done in an hour by four such copiers? ?
Cube wall
The perimeter of one cube wall is 120 meters. Calculate the surface area and the body diagonal of this cube.
Pupils
Four pupils is going via dark hall. Start at one side and have to get to the other side for 17 minutes. They have only one lamp for the trip. The corridor is narrow, they can therefore go up two pupils at a time and go at the slower speed. Each pupil went.
Workers 2
Worker dug the trench for 7 hours, another worker for 10 hours. They recruited to work even one worker more. Digging should be done for 2 hours. For how long would dig third worker alone?
Logistics
Head of logistics department informed the meeting of management of the same item is currently not available in sufficient quantity in all three warehouses of the company. We have the total 135 pieces. It was 37 pieces more in the warehouse No. 3 than in th
Triangular prism
Calculate the volume and surface area of a triangular prism if it is given: a = 6.8 dm. ..Va = 4 dm. (base edge length and base triangle height length) ... ... .v = 23 dm (body height)
Football league
In the football league is 16 teams. How many different sequence of results may occur at the end of the competition?
Tree shadow
The shadow of the tree is 16 meters long. Shadow of two meters high tourist sign beside standing is 3.2 meters long. What height has tree (in meters)?
Similarity
ABC is a triangle wherein a = 4 cm, b = 6 cm, c = 8 cm. Is it similar to the triangle DEF: d = 3 cm, e = 4.5 cm, f = 6 cm? If so, determine the ratio of similarity.
Calcium and citality
The daily dose of calcium obtained using 0.75 liters of milk and 60 grams of cheese. A/ At the morning I drank half a liter of milk. How much cheese I must eatto eat a daily dose of calcium? b / I ate 50 grams of cheese, how much milk I must drink? c /.
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%?
Scale of the map
Determine the scale of the map if the actual distance between A and B is 720 km and distance on the map is 20 cm.
The book
If one day you read p pages, you will read the book 24 days. If you read each day 10 pages more, you would read a book in 16 days. How many pages have the book?
Cube containers
Two containers shaped of cube with edges of 0.7 m and 0.9 m replace a single cube so that it has the same volume as the original two together. What is the length of the edges of the new cube?
Supplementary angles
One of the supplementary angles are three times larger than the other. What size is larger of supplementary angles?
Uranium ore
Uranium ore contains 0.2% of pure uranium and pure uranium contains 0.07% of fissile uranium. How many grams of fissile uranium contains 2800 ton of uranium ore?
Classroom
In a class are 32 pupils. Boys are 8 less than girls. How many boys and girls are in the classroom?
The deposit
Deposit has been placed for one year at an annual rate of 4.5%. After the added interst amount rose to € 2,612.5. Determine initial deposit.
Trapezoid
How long are the trapezoid bases with area 24 cm² and height 3 cm. One base is 3 times longer than the shorter.
Sugar
Sugar factory produced 127 tons of sugar in 1 day at 14% sugar content . How many tons of pure beet sugar factory processed in 1 day?

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