Examples for 9th grade - page 76

  1. Workers
    work_9 9 workers dig a canal 120 meters long for eight hours. For how long would be dig five workers canal 200 meters long?
  2. Probably member
    math_series Look at the series 2,6,25,96,285, ? What number should come next?
  3. Pyramid
    jehlan_4b_obdelnik The pyramid has a base rectangle with a = 6cm, b = 8cm. The side edges are the same and their length = 12.5 cm. Calculate the surface of the pyramid.
  4. Desribed circle to rectangle
    rectangle_in_circle_1 Rectangle with sides 6 cm and 4 cm was circumscribed circle. What part of the content of the circle determined by the circumscribed circle occupies a rectangle? Express in perctentages(%).
  5. 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?
  6. Rainfall
    rain_2 The annual average rainfall in India was in Cherrapunji in the year 1981 26 461 mm. How many hectoliters of water fell on 1 m2? Would fit this amount of water into a cube of three meters?
  7. Cows
    cow_3 Agricultural cooperative has increased the number of housed cows by 14% to 285 units. By how many cows increased agricultural cooperative the number of cows?
  8. Wall diagonal
    cube_6 Calculate the length of wall diagonal of the cube whose surface is 384 cm square.
  9. Exponential equation
    exp_8 Solve for x: (4^x):0,5=2/64.
  10. Content area and percents
    squares_8 Determine what percentage is smaller cube surface, when the surface area of the wall decreases by 25%.
  11. Pyramid four sides
    jehlan_4b_obdelnik_1 In a regular tetrahedral pyramid is a body height 38 cm and a wall height 42 cm. Calculate the surface area of the pyramid; the result round to square centimeters.
  12. Olympics metals
    olympics In how many ways can be win six athletes medal positions in the Olympics? Metal color matters.
  13. The cylinder base
    valec_4 The cylinder with a base of 8 dm2 has a volume of 120 liters. From a cylinder fully filled with water, 40 liters of water was removed. At what height from the bottom /with precision to dm/ is the water level?
  14. Boxes
    krabice 200 boxes have been straightened in three rows. The first was 13 more than in the second, and in the second was one fifth more than in the third one. How many boxes are in each row?
  15. Two aircraft
    dreamliner Two planes fly to the airport. At some point, the first airplane is away from the airport 98 km and the second 138 km. The first aircraft flies at an average speed of 420 km/h, the second average speed is 360 km/h, while the tracks of both planes are perpe
  16. Candies
    zele-bonbony_1 The price for 1 kg of more expensive candies is 125 CZK. The price for 1 kg of cheaper candy is 100 CZK. We mix two different mixtures of candy. A) The first mixture contains 2 kg more expensive and 0.5 kg cheaper candy. Calculate the price for 1 kg of t
  17. Diagonals in diamons/rhombus
    diamonds Rhombus ABCD has side length AB = 4 cm and a length of one diagonal of 6.4 cm. Calculate the length of the other diagonal.
  18. Football season
    ball_f Dalibor and Adam together scored 97 goals in the season. Adam scored 9 goals more than Dalibor. How many goals scored each?
  19. Trucks
    bricks Three lorries droved bricks. One drove n bricks at once, second m less bricks than the first and third 300 bricks more the first lorry. The first lorry went 4 times a day the largest went 3 times a day and the smallest 5 times a day. How many bricks br
  20. Two sisters
    cd_disc Two sisters together have 54 CDs. 6/8 CDs has younger sister and is equal to 3/5 of CDs older sisters. How many CDs has each of the sisters?

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