Examples for 7th grade (seventh) - page 14

  1. Potatoes
    brambory Potatoes contain 78.6% starch. How many potatoes need to obtain 27 kg of starch?
  2. Paddlers
    vodacky Students of canoeists trip traveled in three days 102 km. Second day traveled 15% more than first day and at the third day 9 km over the second day. How many kilometers traveled each day?
  3. Weight of air
    weighting What is the weight of air in the living room measuring width 5 m length 2 m and height 2.8 m? Air density is ρ = 1.2 kg/m3.
  4. Count of roots
    eggs How many solutions has equation x. y = 7757 with two unknowns on the set of natural numbers?
  5. Intersections
    intersect_circles How many intersections have circles with radius 16 mm and 15 mm, if the distance of their centers is 16 mm.
  6. Company
    team After increasing the number of employees by 15% company has 253 employees. How many employees take?
  7. Water container
    water_1 Container with water weighs 1.48 kg. When we cast 75% of water container of water weight 0.73 kg. How heavy is an empty container?
  8. 3-bracket
    triangle2 May be the largest angle in the triangle less than 20°?
  9. Bureaucracy
    bureaucrat The office was attended by 23 people. 9 of them completed the questionnaire. What is the percentage of all people?
  10. N-gon angles
    ngon2 What is the sum of interior angles 9-gon? What is the internal angle of a regular convex 9-polygon?
  11. Tiles
    tiles_1 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.
  12. School books
    sesity At the beginning of the school year, the teacher gave out 480 books and 220 textbooks. How many students were in the class?
  13. Two workers
    Frog Two workers together execute some work in 10 days. The first worker would have done himself in 20 days. How many days would have done himself a second worker?
  14. Circles
    SquareCircleSquare Area of circle inscribed in a square is 14. What is the area of a circle circumscribed around a square?
  15. Family and age ratios
    family_1 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?
  16. Children pool
    hexagon_prism2 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.
  17. Insurance
    tornado 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.
  18. Quadrant II
    quartes_circle Calculate the radius of the quadrant, which area is equal to area of circle with radius r = 15 cm.
  19. Segments
    segments Line segments 67 cm and 3.1 dm long we divide into equal parts which lengths in centimeters is expressed integer. How many ways can we divide?
  20. Rhombus HP
    rhombus3_1 Calculate area of the rhombus with height 24 dm and perimeter 12 dm.

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