Examples for 9th grade - page 12

  1. Rhombus ABCD
    rhombus6 Rhombus ABCD, |AC| = 42 cm, |BD| = 96 cm. Calculate the perimeter of the rhombus ABCD.
  2. Metals
    metals_2 In the Hockey World Cup play eight teams, determine how many ways can they win gold, silver and bronze medals.
  3. Mortgage
    hypo_real_estate Family XY wants to take the bank mortgage (loan for an apartment/house) in the amount of € 100,000. Bank for processing the mortgage charges a fee of 0.79% of the amount borrowed. How many euros is this fee?
  4. Train and car
    car_vs_train The train and the car started at a constant speed to journey. When the train travels 78 km, the car travels 64 km. How many km travels the train when the car travels 78 km?
  5. Trigonometric functions
    trigonom In right triangle is: ? Determine the value of s and c: ? ?
  6. Diagonal in rectangle
    q In that rectangle ABCD is the center of BC point E and point F is center of CD. Prove that the lines AE and AF divide diagonal BD into three equal parts.
  7. Waiting room
    fly In the waiting room are people and flies. Together they have 15 heads and 50 legs (fly has 6 legs). How many people and flies are in the waiting room?
  8. Pizza
    pizza_1 A school survey found that 9 out of 16 students like pizza. If 5 students are chosen at random, what is the probability that all 5 students like pizza?
  9. Sand pile
    sandpile_1 Auto sprinkled with sand to approximately conical shape. Workers wanted to determine the volume (amount of sand) and therefore measure the circumference of the base and the length of both sides of the cone (over the top). What is the volume of the sand c
  10. 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?
  11. 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?
  12. Cleaners
    clean Milan would clean up the room for 2.5 hours, Eric would take 10 hours. How long they swept the room together?
  13. Gasholder
    gas_holder The gasholder has spherical shape with a diameter 23 m. How many m3 can hold in?
  14. Parachutists
    parasutism Parachutists during freefall firstly held in groups of 4, then of 6, then 9, 12 and finally of 18 members. How many parachutists jump at least should be, if at each group must all be involved.
  15. Reciprocal
    rec_gamma What is the reciprocal of the sum of the reciprocals of 7 and 2?
  16. Ladislav in Amsterdam
    jakob3 Ladislav was reward and went to conference in Amsterdam. Conferense fee was € 2184. Calculate how many books Ladislav could buy at the price of 42 and 28 euros if he don't want fill whole home library and he can buy only 63 books?
  17. Olympics metals
    olympics In how many ways can be win six athletes medal positions in the Olympics? Metal color matters.
  18. Arm
    arm Calculate the length of the arm r of isosceles triangle ABC, with base |AB| = 16 cm and a height v=10 cm.
  19. VAT
    Tax John paid 1000 Euros in store for purchase. Calculate value added tax (VAT), which paid in purchase, if the VAT rate is 20%.
  20. Bits, bytes
    bits Calculate how many different numbers can be encoded in 16-bit binary word?

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