Examples for 9th grade - page 27

  1. Two diggers
    two-diggers There are two diggers. One digger digs a pit 83 hours second gidding 1.4 times faster. a) how long took to dig a pit second digger b) how long took dig together
  2. Elections
    gaspar_billboard In elections candidate 8 political parties. Calculate how many possible ways can the elections finish, if any two parties will not get the same number of votes.
  3. Cars plates
    car_plate How many different licence plates can country have, given that they use 3 letters followed by 4 digits?
  4. Chess
    sachovnica How many ways can select 3 fields on classic chess board with 64 fields, so that fields don't has the same color?
  5. 30-60-90
    30-60-90 The longer leg of a 30°-60°-90° triangle measures 7. What is the length of the shorter leg?
  6. Trapezoid ABCD
    trapezoid_2 Calculate the perimeter of trapezoid ABCD if we know the side c=25, b=16 which is also a height and side d=27.
  7. Ice cream in cone
    Ice-Cream-Cone In the ice cream cone with a diameter of 3.6 cm is 0.9 dl of ice cream. Calculate the depth of the cone.
  8. Field with vegetables
    irrigation Field planted with vegetables has shape of a rectangular isosceles triangle with leg length of 24 m. At the vertices of the triangle are positioned rotating sprinklers with a range of 12 m. How much of the field sprinkler doesn't irrigated?
  9. Chicken
    sliepka I threw three chicken for a handful of grains and I noticed that it eat in a ratio of 8:7:6 and two of them grabbed 156 grains. How many grains have fought that chicken?
  10. Flowerbed 2
    flowerbed Around the square flower bed in a park is sidewalk 1.4 m wide. The area of ​​this sidewalk is 125 m2. What is the area of the flowerbed?
  11. Diamond ABCD
    kosoctverec2 In the diamond ABCD is the diagonal e = 24 cm and size of angle SAB is 28 degrees, where S is the intersection of the diagonals. Calculate the circumference of the diamond.
  12. RT and ratio
    triangles Right triangle whose cathetus are in a ratio 6:17 has hypotenuse 47 m long. How long are cathetus?
  13. Cube - wall
    cubes_2 V kocke ABCDEFGH je ?. Aký je povrch kocky?
  14. Bath
    bathroom In the bath is 30 liters of hot water. Then added 38 liters of cold water at temperature of 17 °C decreased temperature of water to 48 °C. What was the initial temperature of the hot water?
  15. Father and son
    father_sin Father is three times older than his son. 12 years ago father was nine times older than the son. How old are father and son?
  16. Water
    storm_1 On the lawn which has area 243 m2 rained 5 mm of water. How many liters of water rained?
  17. Exam average
    vysvedcenie_2 Average of marks that have on the certificates students of 8.A class in mathematics is exactly 2.45. If we did not add 1 and 3 of sutdents Michael and Alena, who arrived a month ago, it would average exactly 2.5. Determine how many students have class 8.
  18. The body
    body_cubes The body on the figure consists of cubes with an edge length 10 cm. What surface has this body?
  19. Diagonal
    rectangles2 Diagonal of the rectangle has length 14 cm. Angle between diagonal and londer sife of rectangle is 37°. Calculate area of the rectangle.
  20. Mother and daughter
    mom_daughter Three years ago mother was three times older than daughter. After nine years she will be only twice old. How old is mother (and daughter)?

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