Reason - examples - page 27

  1. Cards
    cards_2 Suppose that are three cards in the hats. One is red on both sides, one of which is black on both sides, and a third one side red and the second black. We are pulled out of a hat randomly one card and we see that one side of it is red. What is the probabi
  2. Tree shadow 3
    tree3_1 A 2-meter rod casts a shadow 3.2 m long. How high is a tree with a shadow of 14.4 m ?
  3. Bags
    kufor The first bag has a weight of 18 kg, the second bag is a one-third lighter than the first and the third bag has three times less the weight of all three bags together. Determine their weights.
  4. Televisions
    tvs.JPG Television is the fifth most expensive and tenth cheapest TV. How many different TVs are in stores?
  5. Factory
    factory_1 In the factory workers work in three shifts. In the first inning operates half of all employees in the second inning and a third in the third inning 200 employees. How many employees work at the factory?
  6. Apples 5
    apples_7 In six crates are 45 kg of apples. In five crates were the same amounth and in one crate was 3 kg of apples more. How many kg of apples were in each crate?
  7. Krkonose CZ
    krkonose Tourist's rod on the tourist route in the Krkonose was 1/5 of its length into the ground. Snow fell in winter and 1/3 of the length of the rod remained above the snow. Find the height of the snow if the length of the part above the snow is 32 cm greater t
  8. Two ages
    twodigits_1 Gabrielle is 9 years younger than Mikhail. The sum of their ages is 87. What is Mikhail's age?
  9. Potatoes 6
    zemiaky_5 The farmer brought potatoes to the market. In the first hour he sold two-fifths of the potatoes brought, in the second hour he sold five-sixth of the remaining potatoes, and in the third hour he had sold the last 40kg of potatoes. How many kg of potatoes d
  10. Pets in ZOO
    chicken_3 The zoo have run for pets. They are chickens, pigs and cow. Altogether there has 20 heads and 60 feet. How many chickens and piglets are there?
  11. Chairs
    chairs Determine the number of seats in the seventh row and ninth row, if 3rd row has 14 seats and in every next row of seats has five more than the previous row.
  12. Family
    family_14 Mom is 42 years old and her daughters 13 and 19. After how many years will mother as old as her daughter together?
  13. Hockey match
    football_2 The hockey match ended with result 3:1. How many different storylines may have the match?
  14. Banknotes
    ducat $ 1390 was collected. How much was in $20 notes and how many in $50 notes in that order? How many solutions exists?
  15. Repair company
    servis The company repairs cars. The first day repair half of the contract second day, the half of the rest and third day 8 residue cars. How many total cars company repaired?
  16. Four integers
    tiles2 Fnd four consecutive integers so that the product of the first two is 70 times smaller than the product of the next two.
  17. The plan
    zber Students have collected 48 kg of paper which is 16% of the plan. How many kg of paper still have to collect to fulfill the plan?
  18. Variable
    eq2_12 Find variable P: PP plus P x P plus P = 160
  19. Candy - MO
    cukriky_4 Gretel deploys to the vertex of a regular octagon different numbers from one to eight candy. Peter can then choose which three piles of candy give Gretel others retain. The only requirement is that the three piles lie at the vertices of an isosceles triang
  20. Mushrooms
    huby_3 Fresh mushrooms contain 90% water, dried only 12%. How many kilograms of fresh mushrooms are needed for 5kg dried?

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