Examples for 9th grade

  1. Three siblings
    brothers Three siblings have birthday in one day-today. Together they have 35 years today. The youngest is three years younger than middle and the oldest is 5 years older than middle. How old is each?
  2. Friends
    friends2 Some friends had to collect the sum 72 EUR equally. If the three refused their part, others would have to give each 4 euros more. How many are friends?
  3. Concentration
    ocet_1 How 0.5 liters of 8% vinegar diluted to a concentration of 20 hundredths % of vinegar? How many liters of water must be pour?
  4. Vinegar
    vinegar_1 What percentage vinegar we get if we mix 1 if dm³ eight percent vinegar with 1.5 dm³ six percent vinegar?
  5. Cuboid - complicatef
    cuboid_7 Three walls of the same cuboid has content 6 cm2, 10 cm2 and 15 cm2. Calculate the volume of the cuboid.
  6. Apples 2
    apples_2 How many apples were originally on the tree, if the first day fell one third, the second day quarter of the rest and on tree remained 45 apples?
  7. Three numbers
    numbers_9 Find three numbers so that the second number is 4 times greater than the first and the third is lower by 5 than the second number. Their sum is 67.
  8. 12 Moons
    12_mesicku Good Marry came to ask twelve moons for help with collecting strawberries. All twelve moons 1200 strawberries picked in 20 minutes. But lazy months July and August cease tear after 5 minutes. How many minutes in total will take collect strawberries?
  9. Trees
    trees_1 Loggers wanted to seed more than 700 and less than 800 trees. If they seed in rows of 37, left them 8 trees. If they seed in rows of 43, left the 11 trees. How many trees must seed ?
  10. 4side pyramid
    ihlany Calculate the volume and surface of 4 sides regular pyramid whose base edge is 4 cm long. The angle from the plane of the sidewall and base plane is 60 degrees.
  11. Password dalibor
    lock Kamila wants to change the password daliborZ by a) two consonants exchanged between themselves, b) changes one little vowel to such same great vowel c) makes this two changes. How many opportunities have a choice?
  12. Triangular pyramid
    trojboky_ihlan Determine the volume and surface area of a regular triangular pyramid having a base edge a=20 cm and a lateral edge b = 35 cm
  13. Principal and interest
    bank_pig Peter put € 270 principal into bank and at the end of the year on account was € 282. To what annual interest rate that Peter had deposited money in the bank?
  14. Diamond
    diagonals-rhombus Calculate the length of the two diagonals of the diamond if: a = 13 cm v = 12 cm
  15. Water pool
    basen_2 Pool with volume 990hl completely filled, if water flows by one tap 8 hours and by second tap 6 hours. First tap give 10hl more than second per hour. How many hl flows in each of them in an hour?
  16. Triangle IRT
    triangles_5 In isosceles right triangle ABC with right angle at vertex C is coordinates: A (-1, 2); C (-5, -2) Calculate the length of segment AB.
  17. Pages of book
    books_2 Lenka calculated that if every day to read 16 pages of the book, read a book a day earlier than had read only 14 pages a day. How many pages has this book?
  18. Reservoir
    cylinder_Au 6 m long reservoir has a diameter of 2.2 m. What is its surface area in square meters?
  19. Rectangle
    rectangle_circle The rectangle is 18 cm long and 10 cm wide. Determine the diameter of the circle circumscribed to rectangle.
  20. Percent chaining
    meter_1 Calculate 20% from 70% from 80 km

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