Examples for 7th grade (seventh) - page 14

1. Circles Area of circle inscribed in a square is 14. What is the area of a circle circumscribed around a square?
2. Family and age ratios Age of father and son are in the ratio 10:3; age of father and daughter are in the ratio 5:2. How old is father and son, if daughter is 20 years old? In what ratio is age sister and brother?
3. Bureaucracy The office was attended by 23 people. 9 of them completed the questionnaire. What is the percentage of all people?
4. Tiles The room has dimensions 12 m and 5.6 m. Determine the number of square tiles and their largest possible size to cover them room's floor.
5. N-gon angles What is the sum of interior angles 9-gon? What is the internal angle of a regular convex 9-polygon?
6. Insurance The owner of the house is insured against natural disasters and pays 0.04% annually of the value of house 77 Eur. Calculate the value of the house. Calculate the probability of disaster, if you know that 48% of the insurance is to pay damages.
7. Children pool The bottom of the children's pool is a regular hexagon with a = 60 cm side. The distance of opposing sides is 104 cm, the height of the pool is 45 cm. A) How many liters of water can fit into the pool? B) The pool is made of a double layer of plastic film. Convert magnitude of the angle α = 9°39'15" to radians: Calculate the radius of the quadrant, which area is equal to area of circle with radius r = 15 cm.
10. Perpendicular What is the slope of the perpendicular bisector of line segment AB if A[-4,-5] and B[1,-1]?
11. Rhombus HP Calculate area of the rhombus with height 24 dm and perimeter 12 dm.
12. Supermarket cashiers When at the supermarket are opened only 2 cash people waiting in the front approximately 12 minutes. How many will shorten the average waiting time in a front where supermarket open another three cashiers?
13. Trains for people It is said that the train is synonymous to delay. Calculate the average speed of travel by train long 85 km, with regular train leave at 7:00 and arrive at 8:18, but train is late and has departure at 8:10 and arrive at 9:27.
14. Certificate There is 31 students in a class. From mathematics was'nt worse mark than 2. Average mark in mathematics was 2. How many students have mark 1 and how many mark 2?
15. Snow Snow fell overnight layer of thickness 19 cm. In the morning I had to clear a path 69 m long and one meter wide. How many cubic meters of snow I clear? How many kilos was it? (1 m3 fresh snow weighs 350 kg)
16. Pine wood From a trunk of pine 6m long and 35 cm in diameter with a carved beam with a cross-section in the shape of a square so that the square had the greatest content area. Calculate the length of the sides of a square. Calculate the volume in cubic meters of lum
17. Apartments Apartment on the first floor was 10% more expensive than the same apartment on the second floor. The difference was 105 Kc annually. Calculate the annual rent of the apartment in the first floor and from apartment on the second floor.
18. Height Calculate height of the equilateral triangle if its perimeter is 8?
19. University bubble You'll notice that the college up slowly every other high school. In Slovakia/Czech republic a lot of people studying political science, mass media communication, social work, many sorts of management MBA. Calculate how many times more earns clever 25-year
20. Family Martin has just as brothers as sisters. His sister Jana but has 2 times more brothers than sisters. a) How many children are in this family? b) How many boys and how many girls are in the family?

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