Examples for 9th grade - page 43

  1. Slope of the pool
    swimming_pool Calculate slope (rise:run) of the bottom of swimming pool long 40 m. Water depth at beginning of pool is 1.15 m (for children) and depth at end is 1.92 m (for swimmers). Slope express as percentage and as angle in degrees.
  2. Rectangles - sides
    rectangles_2 One side of the rectangle is 25 cm longer than second. Shortens longer side by 14 cm and extend shorter by 13 cm increases the area of the rectangle by 130 cm2. What are the dimensions of the original rectangle?
  3. Two wine
    wines In 2:1 mix wine solution cost 4.1 USD. In 1:2 mix wine solution cost 4.5 USD. How much cost liter of each wine?
  4. Lid
    drywell What is the weight of concrete cover (lid) to round shape well with a diameter 1.3 m, if the thickness of the cover is 15 cm? 1 m3 of concrete weighs 2190 kg.
  5. Tank
    barrel_1 In the middle of a cylindrical tank with a bottom diameter 350 cm is standing rod which is 31 cm above the water surface. If we bank rod its end reach surface of the water just by the tank wall. How deep is the tank?
  6. Ray
    luc-slnka Light ray loses 1/19 of brightness passing through glass plate. What is the brightness of the ray after passing through 3 identical plates?
  7. Road
    route-66 Average climb of the road is given by ratio 1:29. By what angle road average climb?
  8. Hop-garden
    chmelnica The length of the rectangular hop garden Mr. Smith increased by 20% and its width by 20%. What is the percentage change in area of hop garden?
  9. SAS triangle
    triangles2 The triangle has two sides long 7 and 19 and included angle 144°11'59″. Calculate area of this triangle.
  10. Negative percentage
    trabant In 2003, the company had a loss of 25600 Euros. Two years later he was already in profit 25200 Eur. Calculate what percentage of the company increased profits in this two years.
  11. Rhomboid
    parallelogram Calculate the circumference and area of the rhomboid with sides 11 and 17, with their angle 70°.
  12. Described
    desc_circle Calculate perimeter of the circle described by a triangle with sides 418, 59, 430.
  13. Meridian
    Globe What is the distance (length) the Earth's meridian 27° when the radius of the Earth is 6370 km?
  14. Sphere cuts
    sphere_cut At what distance from the center intersects sphere with radius R = 60 plane, if the cut area and area of the main sphere circle is in ratio 3/6.
  15. Right triangle
    righttriangle Legs of right are in ratio a:b = 5:8. Hypotenuse has a length of 16 dm. Calculate the perimeter and area of the triangle.
  16. Clocks
    clocks How long path will walk the end of the clock's minute-hand long 24 cm for 110 minutes? How long will walk in the same time hour-hand?
  17. Angles in triangle
    trigonometry The triangle is ratio of the angles α:β = 8:3. Angle γ is 40° greater than α. What are the size of angles of the triangle?
  18. Profitable bank deposit 2012
    eurocoins Calculate the value of what money lose creditor with a deposit € 7700 for 4 years if the entire duration are interest 2.2% p.a. and tax on interest is 19% and annual inflation is 3.6% (Calculate what you will lose if you leave money lying idle at negative
  19. Two cyclists
    compass_1 Two cyclists started from crossing in the same time. One goes to the north speed 20 km/h, the second eastward at speed 26 km/h. What will be the direct distance cycling 30 minutes from the start?
  20. Doubling
    exp_5 The message is spreading that each day has doubled the number of people who know about it. All know message for 20 days. How long known it eighth people?

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