Examples for 8th grade - page 87

  1. Tank diameter
    cylinder_5 A cylindrical tank has a volume of 60 hectoliters and is 2.5 meters deep. Calculate the tank diameter.
  2. Triangle ABC
    rozbor_triangle Construct a triangle ABC is is given c = 60mm hc = 40 mm and b = 48 mm analysis procedure steps construction
  3. Empty canister
    kanister_1 The canister is filled with oil weight 17 kg. If filled only half weight 9 kg. What weight does my empty canister have?
  4. Factory and divisions
    factory_2 The factory consists of three auxiliary divisions total 2,406 employees. The second division has 76 employees less than 1st division and 3rd division has 212 employees more than the 2nd. How many employees has each division?
  5. Water temperatures
    water2 To 25 liters of water at 50 °C we add 15 liters of water at a different temperature. How many °C should the water be colder than 50 °C so that 40 liters of the water obtained has a temperature 42.5 °C?
  6. Blackberries
    cernice Daniel, Jolana and Stano collected together 34 blackberries. Daniel collected 8 blackberries more than Jolana, Jolana 4 more than Stano. Determine the number blackberries each collected .
  7. Quadrangular pyramid
    komoly Calculate the surface area and volume of a regular quadrangular pyramid: sides of bases (bottom, top): a1 = 18 cm, a2 = 6cm angle α = 60 ° (Angle α is the angle between the side wall and the plane of the base.) S =? , V =?
  8. Tree shadow 3
    stromy_1 What is the diameter of a tree around which is 3m 9dm 7cm long rope wrapped? How big is its cross-sectional area?
  9. Cone
    r_h_cone Calculate the volume of the rotating cone with a base radius 26.3 cm and a side 38.4 cm long.
  10. Acres
    plocha_1 Two hours 24 students harvested chestnuts on 36 acres. How many square meters harvested one student per hour?
  11. Sphere radius
    koule_krychle_2 The surface of the sphere is 60 cm square. Calculate its radius; result round to tenth of cm.
  12. Sales off
    lacnejsie shoes cost x euros. First they are discounted by 50%, and then 25% of the new amount. Determine what percentage of the total cost is cheaper.
  13. Enterprise company
    work 30% of all employees in the enterprise are women. Men are 360 more. How many employees are in the company?
  14. RT perimeter
    rt The leg of the rectangular triangle is 7 cm shorter than the second leg and 8 cm shorter than the hypotenuse. Calculate the triangle circumference.
  15. Raspberries
    maliny_2 Dano had 20 raspberries. John had 90% more raspberries than Dano. Determine how many raspberries have Dano and Juraj together.
  16. Spain vs USA
    balls_bw_1 Spain lost to the US by 4 goals. In the match total fell 10 goals. How many goals gave the Spain and how the United States?
  17. Rectangle 35
    rectangles_13 Find the area of a rectangle when the diagonal is equal to 30 cms and the width is double the length.
  18. Apples
    jablka_4 Apples I picked 600 kg this year. Autumn's apples was 4 times more than the summer. How many kg's I picked the summer and how much winter apples?
  19. The rectangle
    rectangles_6 Determine the area of the rectangle where the length and width are in the ratio 5:2 and its length is 7.5 cm longer than its width. Determine also its length and its width.
  20. One percent
    led One percent of all the lights in the city are LED, the remaining 99% are conventional. Other types are not there. John counted them honestly but he had counted only conventional. After a good dinner he registered numbers and he have notice that from all t

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