Reason - examples

  1. Real estate
    house Residential house has three entrances numbered by odd numbers arithmetic progression. The sum of the two numbers on the corner entrances is 50. Calculate the highest of this three numbers.
  2. MO Z6-6-1
    kruhy_1 Write integers greater than 1 to the blanks in the following figure, so that each darker box was product of the numbers in the neighboring lighter boxes. What number is in the middle box?
  3. 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?
  4. Garden
    zahon_4 Rectangular garden 31 meters 40 centimeters long and 20m30cm wide adjacent with the shorter side with another (fenced) garden and on one longest side is 1 meter wide gate. How many meters of fence is needed to buy? (Estimate, calculate, verify a test ca
  5. Three cats
    three_cats If three cats eat three mice in three minutes, after which time 290 cats eat 290 mice?
  6. Inflation
    dollar What is better for people (employees)? ?
  7. Family
    bigfamily The parents had 2 daughters. Each of them had one brother. How many members family had?
  8. Brick
    brick One brick is 2 kg and half a brick heavy. What is the weight of one brick?
  9. Root
    root_quadrat The root of the equation ? is: ?
  10. 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?
  11. Chickens
    chickens 4 chickens give 4 eggs in 4 days. How many eggs can give 8 chickens for 8 days?
  12. It is rectangular?
    nice_3d Size of two of the angles in a triangle are: α=60°, β=20°. Is it a right triangle?
  13. Seating
    kupe_1 How many ways can 7 people sit on 3 numbered chairs (eg seat reservation on the train)?
  14. Subtraction
    cards1 How many times you can subtract the number 5 from the number 67?
  15. 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)
  16. Wage
    socik Increasing the minimum wage while maintaining the other parameters of the system, unemployment will be:
  17. Stock market
    money_1 Simon one day decided to invest € 88000 to the stock market. After six months he invested July 5 stock markets fell by 56%. Fortunately for Simon from July 5 5 to October 5 his shares have risen by 39%. Simon is then: ?
  18. 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?
  19. 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? ?
  20. Series
    posloupnost_an Andrew wrote this series of numbers: 1,3,7,15, .... n. Which number in the series does not belong? ?

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