The easiest examples

  1. Three cats
    three_cats If three cats eat three mice in three minutes, after which time 140 cats eat 140 mice?
  2. Divisibility
    divisibility Is the number 146025 divisible by 6?
  3. Chocolate
    cokolada Ivan bought 7 same chocolates for 28 Eur. How many euros he pay for 21 chocolates?
  4. One half
    one_half One half of ? is: ?
  5. Inflation
    dollar What is better for people (employees)? ?
  6. Brick
    brick One brick is 6 kg and half a brick heavy. What is the weight of one brick?
  7. Family
    bigfamily The parents had 3 daughters. Each of them had one brother. How many members family had?
  8. Orchard
    orchard 7 trees in 5 lines grows in the orchard. How many trees are in the orchard?
  9. Balls
    balls I have 18 balls and my friend has 32. About how many has my friend more balls?
  10. Cyclist
    cyclist_2 A cyclist passes 88 km in 4 hours. How many kilometers he pass in 8 hours?
  11. Proof PT
    pytagoras Can you easy prove Pythagoras theorem using Euclidean theorems? If so, do it.
  12. Compare
    fraction Compare fractions ?. Which fraction of the lower?
  13. Reverse Pythagorean theorem
    pytagors Given are lengths of the sides of the triangles. Decide which one is rectangular: Δ ABC: 77 dm, 85 dm, 36 dm ? Δ DEF: 55 dm, 82 dm, 61 dm ? Δ GHI: 24 mm, 25 mm, 7 mm ? Δ JKL: 32 dm, 51 dm, 82 dm ? Δ MNO: 51 dm, 45 dm, 24 dm ?
  14. Is right?
    rtriangle Is triangle with sides 51, 56 and 77 right triangle?
  15. Laws
    pyt_triangle From which law follows directly the validity of Pythagoras' theorem in the right triangle? ?
  16. 7 heroes
    7statocnych 5 heroes galloping on 5 horses behind. How many ways can sort them behind?
  17. Holidays
    holidays Calculate how many hours take holidays, if take 7 weeks.
  18. Compare
    compare Compare with characters >, <, =: 85.57 ? 80.83
  19. Vans
    shuttlevan In how many ways can 5 shuttle vans line up at the airport?
  20. Root
    root_quadrat The root of the equation ? is: ?

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