Reason - examples

  1. Z7-I-4 stars 4949
    hviezdicky_mo Write instead of stars digits so the next write of product of the two numbers to be valid: ∗ ∗ ∗ · ∗ ∗ ∗ ∗ ∗ ∗ ∗ 4 9 4 9 ∗ ∗ ∗ ∗ ∗ ∗ 4 ∗ ∗
  2. Two sisters
    cd_disc Two sisters together have 54 CDs. 6/8 CDs has younger sister and is equal to 3/5 of CDs older sisters. How many CDs has each of the sisters?
  3. Brick wall
    plot_zed Garden 70 m long and 48 m wide should surround with wall 2.1 meters high and 30 cm thick. How many we will need bricks if to 1 m³ is needed approximately 300 bricks?
  4. Pyramid Z8–I–6
    pyramida_mo Each brick of pyramid contains one number. Whenever possible, the number in each brick is lowest common multiple of two numbers of bricks lying directly above it. That number may be in the lowest brick? Determine all possibilities.
  5. 2d shape
    semicircles_rect Calculate the content of a shape in which an arbitrary point is not more than 3 cm from the segment AB. The length of the segment AB is 5 cm.
  6. Three cats
    three_cats If three cats eat three mice in three minutes, after which time 270 cats eat 270 mice?
  7. Inflation
    dollar What is better for people (employees)? ?
  8. Family
    bigfamily The parents had 2 daughters. Each of them had one brother. How many members family had?
  9. Brick
    brick One brick is 2 kg and half a brick heavy. What is the weight of one brick?
  10. Root
    root_quadrat The root of the equation ? is: ?
  11. Troops
    regiment Route is long 203 km and the first day first regiment went at an average speed 20 km/h and journey back 19 km/h. The second day went second regiment same route at an average speed 18 km/h there and back. Which regiment will take route longer?
  12. Chickens
    chickens 4 chickens give 4 eggs in 4 days. How many eggs can give 8 chickens for 8 days?
  13. It is rectangular?
    nice_3d Size of two of the angles in a triangle are: α=60°, β=20°. Is it a right triangle?
  14. Seating
    kupe_1 How many ways can 7 people sit on 3 numbered chairs (eg seat reservation on the train)?
  15. Subtraction
    cards1 How many times you can subtract the number 5 from the number 67?
  16. School trip
    school_trip School trip cost 340.8 USD for one class (24 students). How much would cost a trip for two classes? (both classes together have 44 students)
  17. Wage
    socik Increasing the minimum wage while maintaining the other parameters of the system, unemployment will be:
  18. Stock market
    money_1 Simon one day decided to invest € 48000 to the stock market. After six months he invested July 11 stock markets fell by 43%. Fortunately for Simon from July 11 5 to October 11 his shares have risen by 13%. Simon is then: ?
  19. Blood
    krv In human body the blood is about 7.7% body weight. How many kilograms of blood is in the human body with weight 96 kg?
  20. Candies
    bonbons_2 In the box are 12 candies that look the same. Three of them are filled with nougat, five by nuts, four by cream. At least how many candies must Ivan choose to satisfy itself that the selection of two with the same filling? ?

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