Examples for 8th grade - page 49

  1. Crowns
    money_4 1180 crowns is divided into three people that A got 20% less than B and C by 15% more than B. How many got A,B and C?
  2. Truck PRG-BA
    kamionka Truck driving on highway from Prague to Bratislava at average speed of 72 km/h. At the moment when the truck passes 54 kilometer from Prague passenger car departs from Prague which travel to Bratislava at speed 90 km/h. When and where (at waht highway ki
  3. Salary increase
    vyplata Ms. Merry salary increased by 15% and that was 83e. What should pay before the increase?
  4. Janitor
    snow Janitor tosses 26 cm layer of snow on the school grounds for 90 minutes. How many friends would have to call for help if snow needs to have bowled for 15 minutes. We assume that at the same time bow all the same amount of snow.
  5. Feed for horses
    horses In the kennel have feed for two horses for 21 days. The station brought an additional 5 horses. How many days will last the feed for all the horses if they have the same daily ration?
  6. Rectangle
    obdelnik The width of the rectangle is 65% of its length. Perimeter of the rectangle is 132 cm. Determine the dimensions of the rectangle.
  7. Circle inscribed
    inscribed345 Calculate the perimeter and area of a circle inscribed in a triangle measuring 3 , 4 and 5 cm.
  8. 12 Moons
    12_mesicku Good Marry came to ask twelve moons for help with collecting strawberries. All twelve moons 1200 strawberries picked in 20 minutes. But lazy months July and August cease tear after 5 minutes. How many minutes in total will take collect strawberries?
  9. Jane and Miro
    two_men Jane brother Miro is 42 years. And he is three times old as it was Jane when Miro was for so many years as there are now Jane. How old is Jane?
  10. Two numbers
    numbers_1 Find two numbers whose difference and ratio is 10.
  11. Cottages
    chatky The summer camp is 41 cottages. Rooms are for three and for four in them. How many of the 140 campers lives of three?
  12. Sportsman
    lungs A trained athlete is able to exhale after a deep breath still 500 ml of air. At normal inhalation and exhalation is breathing 500 ml of air. Within one minute, one breath and exhaled 19 times. What part of breathing air per day is one exhalation?
  13. Rectangle - sides 3
    stvorec If in the rectangle ABCD we enlarge the side a by 5 cm and decrease the side b by 2 cm, the rectangle area will be reduced by 5 cm². When we decrease the length of the side a by 4 cm and and at the same time we increase the length of side b by 3 cm we incr
  14. Cube 7
    krychle_4 Calculate the volume of a cube, whose sum of the lengths of all edges is 276 cm.
  15. Right triangle trigonometrics
    triangle2 Calculate the size of the remaining sides and angles of a right triangle ABC if it is given: b = 10 cm; c = 20 cm; angle alpha = 60° and the angle beta = 30° (use the Pythagorean theorem and functions sine, cosine, tangent, cotangent)
  16. Quadrant
    quadrants In what quadrant is a 1501° angle?
  17. Three siblings
    brothers Three siblings have birthday in one day-today. Together they have 35 years today. The youngest is three years younger than middle and the oldest is 5 years older than middle. How old is each?
  18. Angles of a triangle
    triangles_9 In the triangle ABC, the angle beta is 15° greater than the angle alpha. The remaining angle is 30° greater than the sum of the angles alpha and beta. Calculate the angles of a triangle.
  19. Freight train
    Freight_train The train carries 525 tons of limestone in 29 wagons. Wagons are 15 tonne and 20 tons. How many is 15 ton and how many is 20 ton wagons?
  20. The farmer
    kombajn The farmer harvested 840 tons of grain in 2006, which was 44% less than in 2005, and one-fifth more than in 2004. How many tons of grain harvested in years 2005 and 2004?

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