Examples for 9th grade - page 52

  1. Mother and daughter 2
    mother_baby The mother is 40 years older than her daughter. How old is the mother if her age is eight thirds age of daughter?
  2. Isosceles trapezoid
    lichobeznik_mo_z8_5 What is the height of an isosceles trapezoid, the base of which has a length of 11 cm and 8 cm and whose legs measure 2.5 cm?
  3. Win in raffle
    tombola_1 The raffle tickets were sold 200, 5 of which were winning. What is the probability that Peter, who bought one ticket will win?
  4. The ship
    ship_1 The ship went upstream speed of 20 km/h in relation to water. River flows at speed 10 km/h. After half an hour, he stopped and returned downstream to the starting point. How long it took way back when even if downstream speed of ship is 20 km/h in relation
  5. Hockey game
    Hockey In the hockey game was made 6 goals. Czech played against Finland. Czechs won 4:2. In what order to fall goals? How many game sequence was possible during the game?
  6. Crates 2
    bedny In 6 crates is 45 kg of apples In  5 crates is equally In 1 in crate is 3 kg more How many kilograms in each crate?
  7. Reduce of the volume
    cubes Calculate how many % reduce the volume of the cube is we reduced length of each edge by 10%.
  8. Stamps and albums
    stamp Michail has in three albums stored 170 stamps. In the first album, there are 14 more than in the second and in the second is by 1/5 less than in the third. How many stamps are in the first album?
  9. Double-track
    vlak_1 On double-track express met with a freight train. Express travel at speed 72 km/h, a freight train at speed 36 km/h. After what time period will be from 9 km apart?
  10. High wall
    mur I have a wall 2m high. I need a 15 degree angle (upward) to second wall 4 meters away. How high must the second wall?
  11. Fog
    fog The car started in fog at speed 30 km/h. After a 12-minute drive, the fog dissipated and the driver drove next 12 minutes distance 17 km. On the last 17 km long again the driving conditions deteriorated and the driver drove the speed of 51 km/h. a) Calcu
  12. Bob and Bobek
    bob_a_bobek At 10h 20min runs Bobek from hat at average speed 12 km/h. At what time must run out Bob at speed 18 km/h to catch him 9 kilometers from the hat?
  13. Gold coin
    gold_munzen Gold coin contains 964 promile pure gold, which is 7.16 g. What is the weight of coin in grams?
  14. Average height
    vyska In a class are 34 students. The average height of students is 165 cm. What will be the average height of students in the classroom when two pupils tall 176 cm and 170 cm moved from this school/class?
  15. Powers
    1power Express the expression ? as the n-th power of the base 10.
  16. Fraction
    polynomial For what x expression ? equals zero?
  17. Chord 4
    circles_5 I need to calculate the circumference of a circle, I know the chord length c=22 cm and the distance from the center d=29 cm chord to the circle.
  18. Shepherd
    sheep_1 The shepherd has fewer than 500 sheep; where they can be up to 2, 3, 4, 5, 6 row is always 1 remain, and as can be increased up to 7 rows of the sheep, and it is not increased no ovine. How many sheep has a shepherd?
  19. Series
    fib Your task is express the sum of the following arithmetic series for n = 14: S(n) = 11 + 13 + 15 + 17 + ... + 2n+9 + 2n+11
  20. Regular triangular prism
    3b_hranol Calculate the surface area of body of regular triangular prism, when the length of its base edge is 6.5 cm and height 0.2 m.

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