Reason - problems

  1. Six on dice
    dices2_1 What is the probability that when throwing two dice will fall at least one six?
  2. Sum on dice
    dices2 We have two dice. What is the greater likelihood of fall a total sum 7 or 8 ? (write 7, 8 or 0 if the probabilities are the same)?
  3. Isosceles triangle
    The perimeter of an isosceles triangle is 112 cm. The length of the arm to the length of the base is at ratio 5:6. Find the triangle area.
  4. Sum or product
    dice_6 What is the probability that two dice fall will have the sum 7 or product 12?
  5. Mow the lawn
    grass_2 Dano would mow the lawn in 12 hours and Milada in 16 hours. How long will take the lawn mow together?
  6. Lines
    lines_4 How many lines can be draw with 8 points, if three points lie on one line and the other any three points do not lie on the same line?
  7. Three-digit
    seven How many three-digit natural numbers do not have the number 7?
  8. Digits
    numbers_48 How many five-digit numbers can be written from numbers 0.3,4, 5, 7 that is divided by 10 and if digits can be repeated.
  9. Ratio of two unknown numbers
    numbers2_23 Two numbers are given. Their sum is 30. We calculate one-sixth of a larger number and add to both numbers. So we get new numbers whose ratio is 5:7. Which two numbers were given?
  10. Direct route
    tourists From two different places A and B connected by a direct route, Adam (from city A) and Bohus (from city B) started at a constant speed. As Adam continued to go from A to B, Bohus turned around at the time of their meeting and at the same speed he returned t
  11. Cars speeds
    cars_17 Distance from city A to city B is 108 km. Two cars were simultaneously started from both places. The speed of a car coming from city A was 2 km/h higher than the second car. What was the speed of each car if they met in 54 minutes?
  12. Odd numbers
    friends4_2 The sum of four consecutive odd numbers is 1048. Find those numbers ...
  13. Testing
    test_3 Students of high school have 10 points for each good solved task. The wrong answer is deducted by 5 points. After solving 20 tasks, student Michael had 80 points. How many tasks did he solve correctly and how many wrong?
  14. Garage
    garaz2 There are two laths in the garage opposite one another: one 2 meters long and the second 3 meters long. They fall against each other and stay against the opposite walls of the garage and both laths cross 70 cm above the garage floor. How wide is the garag
  15. Two ages
    twodigits_1 Gabrielle is 9 years younger than Mikhail. The sum of their ages is 87. What is Mikhail's age?
  16. Tickets 3
    cinema2_5 A total of 645 tickets were sold for the school play. They were either adult tickets or student tickets. There were 55 fewer student tickets sold than adult tickets. How many adult tickets were sold?
  17. Variable
    eq2_12 Find variable P: PP plus P x P plus P = 160
  18. Brick
    brick One brick is 2 kg and half a brick heavy. What is the weight of one brick?
  19. Garden
    garden_1 Area of square garden is 6/7 of triangle garden with sides 96 m, 60 m and 60 m. How many meters of fencing need to fence a square garden?
  20. Trapezoid MO
    right_trapezium The rectangular trapezoid ABCD with right angle at point B, |AC| = 12, |CD| = 8, diagonals are perpendicular to each other. Calculate the perimeter and area of ​​the trapezoid.

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