Examples for 8th grade - page 71

  1. Friends
    Auticka James and Jaroslav are friends. Together they had 48 toy cars. But if John took 8 cars from Jaroslav, Jaroslav will be have 1.5 times more toy cars than James. How many toy cars had Jaroslav and James?
  2. Fuel mileage
    fuel2 You have 3/8 tank of fuel. Estimate fuel consumption @ 6mpg. Estimate speed @ 50mph. Your fuel tank holds 200 gals. Figure out fuel mileage.
  3. Right triangle
    rt_triangle It is given a right triangle angle alpha of 90 degrees beta angle of 55 degrees c = 10 cm use Pythagorean theorem to calculate sides a and b
  4. EQ2
    eq2_4 Solve quadratic equation: ?
  5. Surface area of cylinder
    cylinder_cube Determine the lateral surface of the rotary cylinder which is circumscribed cube with edge length 5 cm.
  6. Triangle ABC
    rozbor_triangle Construct a triangle ABC is is given c = 60mm hc = 40 mm and b = 48 mm analysis procedure steps construction
  7. Fe vs. H2O
    atoms_Fe The volume of what the body of the same weight is greater - iron or water?
  8. Circle's chords
    twochords In the circle there are two chord length 30 and 34 cm. The shorter one is from the center twice than longer chord. Determine the radius of the circle.
  9. Sides of triangle
    triangles Triangle has circumference 42 cm. Side a is 2 times shorter than side b and sice c is 2 cm longer than side a. Determine the sizes of sides of a triangle.
  10. Four friends
    money_10 Four friends shared the money. Vasek got 1/4 of the total amount. Tonda received 1/3 of the rest of the money, Joe got a half from the second residue and Jirka left 80. How much money get together?
  11. Diver and pressure
    tlak Determine what pressures is exposed diver without a suit at a depth of 15 meters, with a small space suit at a depth of 25 meters and a massive suit at a depth of 70 m in water.
  12. Horizontal Cylindrical Segment
    cylinder_horiz How much fuel is in the tank of horizontal cylindrical segment with a length 10m, width of level 1 meter and level is 0.2 meters below the upper side of the tank?
  13. Tetrahedral pyramid
    jehlan_3 It is given a regular tetrahedral pyramid with base edge 6 cm and the height of the pyramid 10 cm. Calculate the length of its side edges.
  14. Trapezium
    trapezium_1 The area of trapezium is 35 cm2. Find its altitude if the bases are 6cm and 8 cm.
  15. Proportion
    proportion write the following proportion 8 is to 64 as to 2 is to x
  16. Sphere vs cube
    koule_krychle_1 How many percent of the surface of a sphere of radius 12 cm is the surface of a cube inscribed in this sphere?
  17. Rotating cone
    kuzel_3 Calculate the volume and the surface area of a rotating cone of base radius r = 2.3 dm and a height h = 46 mm.
  18. Algebrogram
    numbers_26 Solve algebrogram for sum of three numbers: BEK KEMR SOMR ________ HERCI
  19. Hexagonal pyramid
    jehlan_2 Regular hexagonal pyramid has dimensions: length edge of the base a = 1.8 dm and the height of the pyramid = 2.4 dm. Calculate the surface area and volume of a pyramid.
  20. Engine pulley
    remenice The engine has a 1460 rev / min (RPM). Disc diameter is 350 mm. What will be the disc peripheral speed in RPM? Pulleys on the engine has diameter 80mm, on a disc has diameter 160mm.

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