Examples for 8th grade - page 59

Chord 3
What is the radius of the circle where the chord is 2/3 of the radius from the center and has a length of 10 cm?
Divide money 2
Ben and Dan had the same amount of money at the start. When Ben gave 300 to Dan, the ratio of Ben 's money to Dan's money became 2:3. How much money did each have at first?
Draw a trapezoid
Draw a trapezoid if given a = 7 cm, b = 4 cm, c = 3.5 cm, diagonal AC = 5cm. Solve as a construction task.
Kitchen
Kitchen roller has a diameter 70 mm and width of 359 mm. How many square millimeters roll on one turn?
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.
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.
Balls
Michal said to Martin: give me one ball and I'll have twice as you. Martin said: give me 4 and we will have equally. How many balls each have?
Garden pond
Concrete garden pond has bottom shape of a semicircle with a diameter 1.7 m and is 79 cm deep. Daddy wants make it surface. How many liters of water is in pond if watel level is 28 cm?
Cube wall
The perimeter of one cube wall is 120 meters. Calculate the surface area and the body diagonal of this cube.
Triangle
Calculate the area of right triangle ΔABC, if one leg is long 14 and its opposite angle is 59°.
Ladder 2
Ladder 6.4 meters long is positioned in the well such that its lower end is distanced from the wall of the well 1.2 m. The upper part of the ladder is supported on the upper edge of the well. How high is the well?
Prices prices
The meter of the textille was reduced by CZK 42, so 4 meters of the new price was 20 CZK cheaper than 3 meters of the original price. What was the original and new price of the textille?
Brunette
Of the girls who attend primary school are 30% blondes and 70% brunette. 81% blondes and 19% brunette has blue eyes. How many girls attending school altogether if 470 girls has blue eyes?
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? ?
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?
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.
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)
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.
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
Football league
In the football league is 16 teams. How many different sequence of results may occur at the end of the competition?

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