Examples for 7th grade (seventh) - page 8

  1. Air
    air_room_people Room is 40.1 m long, 25.2 dm wide and 369 cm high. How many people can simultaneously be in this room if for hygiene reasons is calculated 5100 dm3 of air per person?
  2. Parquet floor
    Parkett Three workers laid parquet floor for 2.9 hour. The first one would do this work alone 9 hours, the second in 7 hours. For how many hours would fulfill this work the third worker, if he worked alone?
  3. Radius
    green_circle Determine the radius of the circle, if its perimeter and area is the same number.
  4. Cu wire
    medeny-drat Copper wire has a length l = 980 m and diameter d = 8 mm. Calculate the weight if density of copper is ρ = 8500 kg/m3. Result round to one decimal place.
  5. Discount
    sales_discount Product has been discounted twice by 19%. What is the total discount given?
  6. Pool
    bazen Mr. Peter build a pool shape of a four-sided prism with rhombus base in the garden. Base edge length is 8 m, distance of the opposite walls of the pool is 7 m. Estimated depth is 144 cm. How many hectoliters of water consume Mr. Peter to fill the pool?
  7. Seedcake
    pletenky Seedcake costs 44 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros?
  8. Madams
    womans During the spring cleaning ladies going to wash windows. Mother takes wash all the windows 5 hours, the grandmother 3 times longer and Paula wash all windows in 2 hours. How many hours will spend washing the windows this "women's team" if working togethe
  9. Copper sheet
    cuplech The copper plate has a length of 1 m, width 94 cm and weighs 9 kg. What is the plate thickness, if 1 m3 weighs 8715 kg?
  10. Chocholate
    chocolate-xy-axis Table of chocolate is divided into squares on its surface. Lengthwise has 15 squares and widthwise 19 squares. We must chocolate broke into individual squares. How many times we have broke it to get only individual squares? It is not permitted to break
  11. Christmas
    vianoce Calculate how much of the school year (202 days long) take Christmas holidays 19 days long. Expressed as a decimal number and as a percentage.
  12. Cubes
    rubik_cube Cube, which consists of 27 small cubes with edge 4 dm has volume:
  13. Cylinder
    valec Calculate the dimensions of rotating cylindrical container with volume 2 l, if height of container is equal to the diameter of the base.
  14. Triangles
    green_triangle Equilateral triangle with side 40 cm has the same perimeter as an isosceles triangle with arm of 45 cm. Calculate the base x of an isosceles triangle.
  15. Clocks
    clocks How long path will walk the end of the clock's minute-hand long 7 cm for 330 minutes? How long will walk in the same time hour-hand?
  16. LCM
    calc_icon What is the least common multiple of 36, 44, 21?
  17. Expression
    fractions If it is true that ? is:
  18. Vinegar
    vinegar We must dilute 16 liters of 8.8% aqueous vinegar to 4.1% one. How much water is necessary to add?
  19. Crossroads
    crossroad The rectangular crossroads comes passenger car and an ambulance, the ambulance left. Passenger car is at 43 km/h and ambulance 52 km/h. Calculate such a relative speed of the ambulance moves to the car.
  20. OK circle
    circles2 Calculate the radius (circumradius) of the circle described right triangle with hypotenuse long 33 and one cathetus long 17.

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