Examples for 9th grade - page 76

  1. Mushrooms
    huby_3 Fresh mushrooms contain 90% water, dried only 12%. How many kilograms of fresh mushrooms are needed for 5kg dried?
  2. Square
    ctverec_1 Danov's father has a square of 65.25 milligram square of wire with a diagonal. How will the square be big when one mm weighs 7 mg?
  3. Gardens
    pozemky_1 I have a garden in the shape of a square with a side length of 0.02 kilometers. Neighbor has a large garden as well and one side of the garden we share. I'd bought from a neighbor garden that my area of my garden increased to 5 ares. a/ By how many acres I
  4. Probability
    loto What are the chances that the lottery, in which the numbers are drawn 5 of 50 you win the first prize?
  5. Electricity consumption cost
    Temelin4veze1 Last year Karol family reduced its electricity consumption by 31% compared to the previous year and paid CZK 2883 less. How many CZK is electricity last year and how many two year ago?
  6. Friends
    Auticka James and Jaroslav are friends. Together they had 48 toy cars. But if John took 8 cars from Jaroslav, Jaroslav will be have 1.5 times more toy cars than James. How many toy cars had Jaroslav and James?
  7. Difference of two number
    squares2_6 The difference of two numbers is 20. They are positive integers greater than zero. The first number raised to one-half equals the second number. Determine the two numbers.
  8. AP - simple
    progression_1 Find the first ten members of the sequence if a11 = 132, d = 3.
  9. Cylinder
    cylinder_6 In a 1-meter diameter cylinder is 1413 liters of water, which is 60% of the cylinder. Calculate the cylinder height in meters, do not write the units. The resulting value round and write as an integer.
  10. Truck and car
    smetiari At 6h45min the truck started at a speed of 36 km/h. At 7h30m behind it a passenger car. Find the average speed of passenger car if it will catch truck 72 km away from the factory.
  11. Sawmill factory
    rj Peter works in the factory. The bus stop is 10 km from the factory. Therefore, always when the bus arrives for Peter, the driver leaves factory and takes him to work. They are coming at the saw exactly at 8:00. Today the bus arrived 11 minutes earlier and.
  12. EQ2
    eq2_4 Solve quadratic equation: ?
  13. Parallelogram
    kosostvorec_3 Side a of parallelogram is twice longer than side b. Its circumference is 78 dm. Calculate the length of the sides of a parallelogram.
  14. Workers
    okno2_1 Group of workers washing half of the windows of the building in two hours. How long will take half the workers wash all the windows of the building?
  15. Alcohol
    metaxa How many cubic centimeters of 96% alcohol is needed to obtain 0.75 liter of 40% alcohol?
  16. Unknown number 4
    ninth I think number. When I divided its square root by its 1/9, I get a number 1. What number am I thinking?
  17. Three monks
    Bible Three medieval monks has task to copy 600 pages of the Bible. One rewrites in three days 1 page, second in 2 days 3 pages and a third in 4 days 2 sides. Calculate for how many days and what day the monks will have copied whole Bible when they begin Wednesd
  18. AP - simple
    sigma_1 Determine the first nine elements of sequence if a10 = -1 and d = 4
  19. Outer contact of circles
    nakres_2z Construct a circle k1 (S1; 1.5 cm), k2 (S2; 2 cm), and K3 (S3; 2.5 cm) so that they are always two outer contact. Calculate the perimeter of the triangle S1S2S3.
  20. BTC bubble
    btc_2 One of the world's experts in bubbles -- Prof. Robert Shiller, a Yale economist -- said Bitcoin "was an amazing example of a bubble" back in 2014. If you exchange fiat US dollar $100 to BTC in 2010, now in 2017 have value of 72.9 millions dollars. Find.

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