Examples for 8th grade - page 27

  1. Divisors
    one Find all divisors of number 418. How many are them?
  2. Parallelogram
    quadrilateral_parallelogram The perimeter of the parallelogram is 202 cm. The length of one side is 1.2-times longer than the length of the shorter side. What is the length of sides of a parallelogram?
  3. Diameter
    diameter_circle If the endpoints of a diameter of a circle are A(10, -5) and B (8, 7), what is the radius of the circle?
  4. Hurry - rush
    bus_3 At an average speed 10 km/h I will come from the school to the bus stop for 29 minutes. How fast I need to go if I need to get to the bus stop in 21 minutes?
  5. Circumscription
    circles43 Calculate radius of the Circumscribed circle in the rectangle with sides 17 and 16. It can be rectangle inscribed by circle?
  6. Sawdust
    drevo_kmen_rez How many cubic centimeters of wood sawdust is created by cut the tree trunk with a diameter of 38 cm and when the gap width is 6 mm?
  7. Bridge
    bridge_circle The bridge arc has a span 41 m and height 3 m. Calculate the radius of the circle arc of this bridge.
  8. Gauss
    kfgauss Help little C.F. Gauss sum all the integers from 1 to 340.
  9. Angles ratio
    3angle_1 In a triangle ABC true relationship c is less than b and b is less than a. Internal angles of the triangle are in the ratio 5:4:9. The size of the internal angle beta is:
  10. Journey
    Mt-Everest The road from A to B measures 11.5 km. Firstly up the hill, then by level plane and then downhill. Tourist goes uphill at 3 km/h, on the plane 4 km/h and downhill 5 km/h. From point A to B went 2h 54 min back 3h 6 min. How long is the segment of level pla
  11. Vertical prism
    hranoly3 The base of vertical prism is a right triangle with leg a = 5 cm and a hypotenuse c = 13 cm. The height of the prism is equal to the circumference of the base. Calculate the surface area and volume of the prism
  12. Metal alloy
    ocel What is the ratio of metals in the alloy that is in the 50 tonnes of steel to 30 kg nickel?
  13. Tablecloth
    decka I embroider tablecloth in 20 days, if I embroider 3/4 hours a day; I have embroider it for 15 days. How long do I embroider a day?
  14. SAS triangle
    triangles2 The triangle has two sides long 7 and 19 and included angle 144°11'59″. Calculate area of this triangle.
  15. Bomber
    b52 Bomber flies 5 km at 1400 km/h. At what horizontal distance from the target, must pilot drop the bomb to hit the target? Don't care about air resistance and consider the gravitational acceleration g=9.81 m/s2.
  16. Family and age ratios
    family_1 Age of father and son are in the ratio 10:3; age of father and daughter are in the ratio 5:2. How old is father and son, if daughter is 20 years old? In what ratio is age sister and brother?
  17. Aircraft
    aircraft_soviet The aircraft has in a fuel tank 100 hl of aviation fuel and flight consumes 4.3 liters of fuel. Identify the function, which expresses the dependence of the volume of fuel in tank on the track distance plane flew by. How many hectolites of fuel is still i
  18. Two runners
    sprinters_1 Two runners ran simultaneously towards each other from locations distant 21 km. The average speed of the first runner was 1/7 higher than the average speed of the second runner. How long should each ran a 21 km, if you know that they meet after 77 minute
  19. Rectangle
    obdelnik_1 The length of the rectangle are in the ratio 5:12 and the circumference is 238 cm. Calculate the length of the diagonal and area of rectangle.
  20. Work
    dlazba.pg First paver pave pavement for 33 hours. Second for 24 hours. Started first paver and after 5 hours, join the second. How long will they finish pavement?

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