Examples for 9th grade - page 35

  1. Driving school
    bmw-autoskola Driving final exam involving 17 attendants. The exam consists of three parts. 4 fails at test (quiz) and 3 students fails on car skills test on playground (slalom between the cone). The practical part of the test - driving in town in the real traffic - al
  2. Monty Hall
    Monty_open_door Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. W
  3. Mean
    integrales if the mean of the set of data 10, 13, 8, 18, 20, 17, 19, 3, 10, 8, 8, 3, 12, 15, 14, 4, 20, 19, x is 24.36, what is the value of x?
  4. Free fall
    volny_pad Stephen fall from height 5 m. Calculate the speed he hit the ground when falling with acceleration g = 9.81 m/s2
  5. Rotating cone II
    cone Calculate area of surface of rotating cone with base radius r=7 cm and height h=17 cm.
  6. Circle and angle
    arc What is the length of the arc of a circle with radius r = 138 cm with cental angle 2.07 rad?
  7. Hollow sphere
    Xmas_ball Calculate the weight of a hollow brass sphere (density 8.5 g/cm3), if the outer diameter is 10 cm and wall thickness is 3 mm.
  8. Cube - angles
    cube_diagonal_1 Calculate angle between the wall diagonal and cube base. Calculate the angle between the cube body diagonal and cube base.
  9. Right triangle Alef
    r_triangle The perimeter of a right triangle is 132 cm, the hypotenuse is 55 cm long. Determine the lengths of the legs.
  10. Unknown number 23
    cisla_4 Find 2/3 of unknown number, which is two thirds of the 99.
  11. Trapezoid
    lichob_2_1 How long are the trapezoid bases with area 24 cm2 and height 3 cm. One base is 3 times longer than the shorter.
  12. Apples
    jablka_4 Apples I picked 600 kg this year. Autumn's apples was 4 times more than the summer. How many kg's I picked the summer and how much winter apples?
  13. Rings groups
    venn 27 pupils attend some group; dance group attends 14 pupils, 21 pupils sporty group and dramatic group 16 pupils. Dance and sporting attend 9 pupils, dance and drama 6 pupil, sporty and dramatic 11 pupils. How many pupils attend all three groups?
  14. Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  15. Sale off
    percents2_1 Product cost 95 euros before sale off. After sale off cost 74 euros and 10 cents. About what percentage of produt became cheaper?
  16. Fifth member
    arithmet_seq_1 Determine the fifth member of the arithmetic progression, if the sum of the second and fifth members equal to 73, and difference d = 7.
  17. Interst on savings
    ecb_2 The bank offers 1.6% interest. How many euros have to insert at the beginning if we received € 15 on the interest?
  18. PC disks
    diskette Peter has 45 disks in three colors. One-fifth of the disks are blue, red are twice more than the white. How much is blue, red and white disks?
  19. Sweets
    Caramelos We want to prepare 5 kg of sweets for 150 CZK. We will mix cheaper candy: 1 kg for 120 CZK and more expensive candy: 1 kg per 240 CZK. How much of this two types of candy is necessary to prepare this mixture?
  20. Canister
    kanister Gasoline is stored in a cuboid canister having dimensions 44.5 cm, 30 cm, 16 cm. What is the total weight of a full canister when one cubic meter of gasoline weighs 710 kg and the weight of empty canister is 1.5 kg?

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