Examples for 8th grade - page 46

  1. Unions
    odbory_prdel Calculate how much money per year would go to the treasury of unions if 447 thousand employee join unions with an average net salary of 539 euros and if memberhip in union cost 1% of the net monthly salary.
  2. Base
    rotunda Base of building is circle with diameter 39 m. Calculate the circumference of a circular trench witch diameter is 21 cm wider than the diameter of the base.
  3. Cu wire
    medeny-drat Copper wire has a length l = 210 m and diameter d = 10 mm. Calculate the weight if density of copper is ρ = 8500 kg/m3. Result round to one decimal place.
  4. Square Number
    squared-number If to a square of integer number add 49, we get the square of next integer number. What is the original number?
  5. Mean
    integrales if the mean of the set of data 10, 13, 8, 18, 20, 17, 19, 3, 10, 8, 8, 3, 12, 15, 14, 4, 20, 19, x is 24.36, what is the value of x?
  6. Climb
    scenic_road Road has climbing 1:23. How big is a angle corresponds to this climbing?
  7. Sea
    ship How far can you see from the ship's mast, whose peak is at 11 meters above sea level? (Earth's radius is 6370 km).
  8. Sphere
    1sphere Surface of the sphere is 2260 cm2, weight is 52.2 kg. What is its density?
  9. VAT
    tax VAT is a tax which the state artificially betrays goods and services for final consumption. VAT in Slovakia is 20%. Calculate how much percent pay less tax residents of Switzerland, when VAT is only 8%.
  10. Triangle SAS
    triangle_iron Calculate area and perimeter of the triangle, if the two sides are 19 cm and 80 cm long and angle them clamped is 90°.
  11. Crossroads
    crossroad The rectangular crossroads comes passenger car and an ambulance, the ambulance left. Passenger car is at 45 km/h and ambulance 58 km/h. Calculate such a relative speed of the ambulance moves to the car.
  12. Comparing salaries
    eura_5 Spouses compared salaries. Mrs. Janka found that a 20% higher salary than Mr Jaroslav. Together earned € 1,430. How much they earn each of them?
  13. Workers
    work_9 9 workers dig a canal 120 meters long for eight hours. For how long would be dig five workers canal 200 meters long?
  14. Minute
    compass Two boys started from one place. First went north at velocity 3 m/s and the second to the east with velocity 4 m/s. How far apart they are after minute?
  15. UN 1
    bulb2 If we add to an unknown number his quarter, we get 210. Identify unknown number.
  16. Distilled water
    water2_1 Sea water contains 5% salt. How many distilled water should be pour to 40 kg of sea water so that the salt content is 2%. How many kilograms of 2% of sea water we get?
  17. Digging
    Dighole A pit is dug in the shape of a cuboid with dimensions 10mX8mX3m. The earth taken out is spread evenly on a rectangular plot of land with dimensions 40m X 30m. What is the increase in the level of the plot ?
  18. Train expres
    rjet At 8.00 strarted from Bratislava to Poprad express Tatry. Cities are distant 340 kilometers. At the same time started from Poprad express Danube to Bratislava. Express Tatry's average speed is 80 km/h, Danube 90 km/h. At what distance from Poprad trains w
  19. Wallet
    berries From the money that was in my Maria wallet she spent a fifth on the first purchase. From remain money she could buy 2 kg of strawberries. But she bought only 1.5 kg for 60 Kc. How much money was Marie originally in her wallet?
  20. Reduce of the volume
    cubes Calculate how many % reduce the volume of the cube is we reduced length of each edge by 10%.

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