Examples for 9th grade - page 64

  1. Three friends
    pizza_4 Divide 570 euros to three friends so that first will get 50 euros less than the second and third twice more than the first. How many euros will get everyone?
  2. Concentration
    hcl_1 How many grams of 65% and 50% acid is to be mixed to give 240 g acid with a concentration of 60%?
  3. Copper wire
    cu_wire_1 What is the weight of 1000 m copper wire with a diameter of 5 mm when rezistivity p = 8.8 g / cm3?
  4. Algebrogram
    plus_2 Solve algebrogram: mama+anna=vari How many solutions are?
  5. Football league
    football_1 In the 2nd football league plays each of the 16 participants with each opponent twice. For every victory gets 3 points, 1 point for a draw, a defeat none. After the competition was team with 54 points and 12 defeats at 9th place. How many times have won?
  6. Bus and Milan
    motorka The bus started from the village at speed 60 km/h. After one kilometer, when Milan came to bus stop on a motorcycle with grandmother. When they found that bus drove away he try to catch it. At the next stop, a distance of 3km caught up bus. How quickly had
  7. Quadrilateral 2
    quadrilateral Show that the quadrilateral with vertices P1(0,1), P2(4,2) P3(3,6) P4(-5,4) has two right triangles.
  8. Average age
    age_4 The average age of all people at the celebration was equal to the number of people present. After the departure of one person who was 29 years old, average age was again equal to the number present. How many people were originally to celebrate?
  9. Jane
    gift Jane buy gift together for 464 Sk. For tie paid 4.5 times less than in the shirt, but 56 Sk more than for socks. How much she paid for each item in gift?
  10. Digging
    Dighole A pit is dug in the shape of a cuboid with dimensions 10mX8mX3m. The earth taken out is spread evenly on a rectangular plot of land with dimensions 40m X 30m. What is the increase in the level of the plot ?
  11. Suzan
    eliska My daughter reaches X years in X squared, said Suzan father in 2009 during the celebration of her birthday. When will given fact become reality and how many years at that time will have Suzan?
  12. Painting
    malovka The room is long 50 meters and wide 60dm and 300 cm high. Calculate how much it will cost painting if area of windows and doors is 15% of the total area. One square meter cost 50cents.
  13. Real estate
    house Residential house has three entrances numbered by odd numbers arithmetic progression. The sum of the two numbers on the corner entrances is 50. Calculate the highest of this three numbers.
  14. Sphere vs cube
    koule_krychle_1 How many percent of the surface of a sphere of radius 12 cm is the surface of a cube inscribed in this sphere?
  15. Four swords
    fight Obelix has three helmets, four swords and five shields. How many swords must make at the blacksmith forge Metallurgix to be able to walk another 90 days in unique armor?
  16. Numbers at ratio
    number-2_2 The two numbers are in a ratio 3:2. If we each increase by 5 would be at a ratio of 4:3. What is the sum of original numbers?
  17. Variations
    pantagram Determine the number of items when the count of variations of fourth class without repeating is 38 times larger than the count of variations of third class without repetition.
  18. Painter
    painting_1 How many euros we will pay for repainting the room shaped cuboid with a length of 4.5 meters, width of 2.5 meters and a height of 3 meters, if for 1 m2 with paint we pay € 1.5?
  19. Lines
    lines_4 How many lines can be draw with 8 points, if three points lie on one line and the other any three points do not lie on the same line?
  20. Trucks
    truck_big Truck take you the some amount of clay in 30 hours. Second truck in 40 hours. Trucks carted the clay away some time together then the second truck broke down and the first one completed the job in five hours. What time worked together?

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