Examples for 9th grade - page 70

  1. Cuboid - ratios
    kvader11 The sizes of the edges of the cuboid are in the ratio 2: 3: 5. The smallest wall have area 54 cm2. Calculate the surface area and volume of this cuboid.
  2. Addends
    two Number 118 divide into two addends, so first addend is 69 greater than 75% of the second addend.
  3. Combinations of sweaters
    sveter I have 4 sweaters two are white, 1 red and 1 green. How many ways can this done?
  4. Potatoes
    zemiaky_3 Daniela and Michael would jointly dug potatoes for 7.5 hours. But if Daniela was working alone she would take 2.5 hours more as if he were working with Michael. Determine how much for the work done by Michael himself and how much Daniela herself.
  5. Digits
    numbers_48 How many five-digit numbers can be written from numbers 0.3,4, 5, 7 that is divided by 10 and if digits can be repeated.
  6. Book read
    books_12 If Petra read 10 pages per day, she would read the book two days earlier than she read 6 pages a day. How many pages does a book have?
  7. Theatro
    divadlo_1 Theatrical performance was attended by 480 spectators. Women were in the audience 40 more than men and children 60 less than half of adult spectators. How many men, women and children attended a theater performance?
  8. Three figures - numbers
    numbers34 The sum of three numbers, if each is 10% larger than the previous one, is 662. Determine the figures.
  9. Candy
    bonbons_5 The price for 1kg of more expensive candy is 125 CZK. The price for 1kg of cheaper candy is 100 CZK. We make two different blends of candy. And now. The second blend contains 2kg of more expensive candy and several kg of cheaper candy. The price per 1 kg o
  10. Saving per cents
    penize.JPG The first day I save 1 cent and every next day cent more. How many I saved per year (365 days)?
  11. Centre of mass
    centre_g_triangle The vertices of triangle ABC are from the line p distances 3 cm, 4 cm and 8 cm. Calculate distance from the center of gravity of the triangle to line p.
  12. Diameters of circles
    circle5_1 How many percent of the area of a larger circle is a smaller circle if the smaller circle has a diameter 120 mm and a larger one has a diameter 300 mm?
  13. Hexagonal prism 2
    hranol6b The regular hexagonal prism has a surface of 140 cm2 and height of 5 cm. Calculate its volume.
  14. Contestants
    avg_1 In the competition it was possible to get 0-5 points. In fact, 5 contestants of the 15 best contestants has earned 5 points or 4 points (which have won 10 contestants). The number of contestants who earned 3 points was the same as the number of contestan
  15. Cost reduction
    mp3_1 Two MP3 players whose price was equal to originally have been discounted the first by 20%, the second by 35%. After the price reduction was the difference in their prices 750, - CZK. What was the original price of each of the two players?
  16. Family parcels
    map_4 In father will he divided the land so that the older son had three bigger part than younger son. Later elder son gave 2.5 ha field to younger and they had both the same. Determine the area of family parcel.
  17. Two numbers
    fractal_6 The sum of the two numbers is 1. Find both numbers if you know that half of the first is equal to one seventh of the second number.
  18. Cruise liner
    parnik_1 Cruise liner runs along the river between points A and B. The journey downstream takes 40 minutes 1 hour upriver. The flow rate of the river is 3 km/h. What is the speed of cruise liner?
  19. Is right triangle
    triangle_1111_4 Decide if the triangle XYZ is rectangular: x = 4 m, y = 6 m, z = 4 m
  20. Isosceles trapezoid
    rr_lichobeznik Calculate the circumference and the contents of the isosceles trapezoid if you know the size of the bases is 8 and 12 cm and the size of the arms is 5 cm.

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