Examples for 9th grade - page 49

  1. 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?
  2. 3 days
    kontrolor Worker checked 2,950 products in 3 days. Second day checked 25% more than the first day. The third day 15% more products than the second day. How many products he checked in each day.
  3. V - slope
    verticals The slope of the line whose equation is 8x +8 = 0 is
  4. 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?
  5. 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?
  6. Solution
    chemia What amount of 80% solution and what amount of water is needed to mix in order to obtain two liters of 60% solution of this mixture?
  7. Parallelogram ABCD
    paralleogram_1 The area of parallelogram ABCD is 41 cm2. Points M and N are the midpoints of the sides AB and BC. What is the area of a quadrilateral MBND?
  8. Statistics
    lines_globe The sum of all deviations from the arithmetic mean of the numerical sequence 1, 7, 7, 26, 43, 47, 80, 96, 113, 120 is:
  9. Candelas
    sviecky We burned two unequally thick and long candles. Longer burnt for three and a half hours and shorter for five hours. After two hours of burning it was identical. How many times was longer candle longer then shorter?
  10. Chocholate pyramid
    pyramid_choko How many chocolates are in the third shelf when at the 8th shelf are 41 chocolates in any other shelf is 7 chocolates more the previous shelf.
  11. Reservoir
    cylinder_Au 6 m long reservoir has a diameter of 2.2 m. What is its surface area in square meters?
  12. Speedometer
    lotus The speedometer of a car reads 78 km/h. It's accurate to within 4.2% What is the maximum possible error?
  13. Siblings
    tri-sourozenci Three siblings had saved up a total of 1,274 CZK. Peter had saved up to 15% more than Jirka and Hanka 10% less than Peter. How much money they saved each one of them?
  14. Quadratic function
    eq2_graph It is given a quadratic function y = -5x2+12x+c with unknown coefficient c. Determine the smallest integer c for which the graph of f intersects the x-axis at two different points.
  15. 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?
  16. Rhombus A2p
    kosostvorec Rhombus area is 13 cm2 and its height is 5cm long . Determine a perimeter of this rhombus.
  17. Copy typist
    pisaci_stroj Typist for 12 hours rewritten 15% of the manuscript. After how many hours he will done 35% of the manuscript?
  18. Welders
    svarec Welder do the job for six hours, the second one for 8 hours. How long do the job third welder if all together can do job in 2 hours?
  19. Apples
    apples_5 A 2 kg of apples cost a certain sum of money. This sum is equal to the amount of kilograms for which we pay 72 CZK. How much is 1 kg of apples?
  20. Reduce of the volume
    cubes Calculate how many % reduce the volume of the cube is we reduced length of each edge by 10%.

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