Examples for 7th grade (seventh) - page 14

  1. Hiker
    hiker Hiker went half of trip the first day, the third of trip the second day and remaines 15 km. How long trip he planned?
  2. Train from Prague
    train_cd_1 First train from Prague started at 8:00 hour at 40 kilometers per hour. Train from Ostrava started at 9:20 at 80 km per hour. In how many hours and how far from cities with trains meet if the distance of cities is 400 km.
  3. Exhibition
    skola_vola The teacher paid for 280 Kč for 4.A students for admission to the exhibition. How many students were on the exhibition?
  4. Water tank
    akvarium_1 Water tank shape cuboid has a width of 3.1 m and length twice larger. How high will reach water if water flow into 13 liters of water per second during 16 minutes?
  5. Two workers
    mame_nizke_mzdy The first worker completed the task by himself in 9 hours, the second in 15 hours. After two hours of joint work left first worker to a doctor and the second finished the job himself. How many hours worked second worker himself?
  6. The bridge
    circle_dam Across the circle lakepasses through its center bridge over the lake. At three different locations on the lake shore are three fishermen A, B, C. Which of fishermen see the bridge under the largest angle?
  7. Box
    uhlopriecka Calculate the angle between box base 9 x 14 and body diagonal length 18.
  8. Balance
    balance_weight The rod are 1.9 m long hanging weights 4 kg and 1 kg on ends. Where are centre of rod (distance from weight 4 kg) to be in balance?
  9. Workers
    jumps Workers digging a jump pit in the school yard. Pit has a cuboid shape with a length 12 m, a width 20 dm and depth 36 cm. They excavate 0.4 cubic meters of soil an hour. How much time (hours and minutes) is need to the excavate this pit?
  10. Do you solve this?
    rectangles_4 Determine area S of rectangle and length of its sides if its perimeter is 102 cm.
  11. Opposite numbers
    plus_minus Calculate opposite numbers (additive inverse) to given ones:
  12. Car
    journey Car travels 1/3 of the trip on the first day, second day 2/5 of the trip and left even 340 km for next days. How long is the trip?
  13. Rectangle A2dim
    Rectangle Calculate the side of the rectangle, if you know that its area is of 2590 m2 and one side is 74 m.
  14. Map
    mapa_bce Forest has an area of ​​36 ha. How much area is occupied by forest on the map at scale 1:500?
  15. Potatoes
    brambory Potatoes contain 78.6% starch. How many potatoes need to obtain 27 kg of starch?
  16. 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.
  17. 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?
  18. Count of roots
    eggs How many solutions has equation x. y = 7757 with two unknowns on the set of natural numbers?
  19. Intersections
    intersect_circles How many intersections have circles with radius 16 mm and 15 mm, if the distance of their centers is 16 mm.
  20. Company
    team After increasing the number of employees by 15% company has 253 employees. How many employees take?

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