Reason - examples - page 8

  1. Euler problem
    euler Someone buys a 180 tolars towels. If it was for the same money of 3 more towels, it would be 3 tolars cheaper each. How many were towels?
  2. Water container
    water_1 Container with water weighs 1.48 kg. When we cast 75% of water container of water weight 0.73 kg. How heavy is an empty container?
  3. Intersections
    intersect_circles How many intersections have circles with radius 16 mm and 15 mm, if the distance of their centers is 16 mm.
  4. Two workers
    Frog Two workers together execute some work in 10 days. The first worker would have done himself in 20 days. How many days would have done himself a second worker?
  5. Gardens
    garden_3 The garden has the square shape with circumference 124 m. Divide it into two rectangular gardens, one should circumference 10 meters more than the second. What size will have a gardens?
  6. 9.A
    exam 9.A to attend more than 20 students but fewer than 40 students. A third of the pupils wrote a math test to mark 1, the sixth to mark 2, the ninth to mark 3. No one gets mark 4. How many students of class 9.A wrote a test to mark 5?
  7. Family and age ratios
    family_1 Age of father and son are in the ratio 10:3; age of father and daughter are in the ratio 5:2. How old is father and son, if daughter is 20 years old? In what ratio is age sister and brother?
  8. Tiles
    tiles_1 The room has dimensions 12 m and 5.6 m. Determine the number of square tiles and their largest possible size to cover them room's floor.
  9. Father and son
    father_sin Father is three times older than his son. 12 years ago father was nine times older than the son. How old are father and son?
  10. N-gon angles
    ngon2 What is the sum of interior angles 9-gon? What is the internal angle of a regular convex 9-polygon?
  11. Party
    party-informatikov At party overyone clink with everyone. Together, they clink 171 times. How many people were at the party?
  12. Rectangle
    rectangles_1 The perimeter of the rectangle is 22 cm and content area 30 cm2. Determine its dimensions, if the length of the sides of the rectangle in centimeters is expressed by integers.
  13. Trains for people
    757_rusen It is said that the train is synonymous to delay. Calculate the average speed of travel by train long 85 km, with regular train leave at 7:00 and arrive at 8:18, but train is late and has departure at 8:10 and arrive at 9:27.
  14. Baker
    pekar The baker makes from 10 kg of flour 12 kg dough. How much flour he need to make a 100 kg dough?
  15. Lines
    lines_1 In how many points will intersect 14 different lines, where no two are parallel?
  16. Family
    family_2 Martin has just as brothers as sisters. His sister Jana but has 2 times more brothers than sisters. a) How many children are in this family? b) How many boys and how many girls are in the family?
  17. Salary
    platy Calculate equivalent annual salary to hourly salary $ 19. Assume a 42-hour work week.
  18. Education for free
    skola The Slovakia circulates a lot of myths, particularly ideas about what must be free. For example - education should be free - children of poor parents should know at least read and write. Calculate how much a student would have to pay per hour of teaching,
  19. Circle
    circles_2 Circle is given by centre on S[-7; 10] and maximum chord 13 long. How many intersect points have circle with the coordinate axes?
  20. Lottery
    loteria_1 The lottery is 60000 elk in which 6200 wins. What is the probability that the purchase of 12 elks won nothing?

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