Inequalities - examples

  1. Quadratic inequation
    eq2_8 If 5x + x² > 100, then x is not
  2. 3-bracket
    triangle2 May be the largest angle in the triangle less than 70°?
  3. 3-bracket 2
    1triangle May be the smallest angle in the triangle greater than 20°?
  4. 3-bracket 3
    triangle_3 Two angles in a triangle are 80° and 50°. Has triangle at least two equal sides?
  5. Intersections
    intersect_circles How many intersections have circles with radius 12 dm and 17 dm, if the distance of their centers is 20 dm.
  6. Reciprocal
    inverse It is true (prove it) that if a> b> 0: ?
  7. QuizQ
    green_triangle_1 An isosceles triangle has two sides of length 9 dm and 35 dm. How long is a third side?
  8. Party
    party-informatikov At party overyone clink with everyone. Together, they clink 406 times. How many people were at the party?
  9. Report card
    vysvedcenie_1 Ivor hit 1× grade 5 at the beginning of the school year. How many times must now catch grade 1 to get grade 2 on report card?
  10. Athletes
    spartakiada_2 Athletes standing in rows of eight. Ivan estimated that athletes are more than 120. Peter claimed that there are fewer than 130. Both are right. How many are athletes?
  11. Grass garden
    koseni Mr. Grass would itself be mowed garden for 5 hours. His son Michael could do it for 7 hours. They agreed that they wake up at 5 am and begins to mow together. Ms. Grass needs drive into town at 8.30. Michael says that at that time they're done with work..
  12. Dining tables
    stolik In the dining room are tables with 4 chairs, 6 chairs, 8 chairs. How many diners must be at least to be occupy all tables (chairs) and diners are more than 50?
  13. Line
    negative_slope Straight line passing through points A [-3; 22] and B [33; -2]. Determine the total number of points of the line which both coordinates are positive integers.
  14. Lion or virgin
    1_kcs We toss coin, every throw fits lion or a virgin with equal probability 1/2. Determine how much at least we have to make throws that with probability 0.9 lion fell at least once.
  15. Right triangle Alef
    r_triangle The perimeter of a right triangle is 132 cm, the hypotenuse is 55 cm long. Determine the lengths of the legs.
  16. Trees
    trees_1 Loggers wanted to seed more than 700 and less than 800 trees. If they seed in rows of 37, left them 8 trees. If they seed in rows of 43, left the 11 trees. How many trees must seed ?
  17. Rates
    gas_meter When gas consumption, the consumer may choose one of two rates: rate A - which pays 0.35 € per 1 m3 of gas a flat monthly fee of 3.6 € (regardless of consumption) rate B - which pays 0.295 € per 1 m3 of gas a flat monthly fee of 8.3 € From what monthl
  18. R triangle
    right_triangle_1 Calculate the area of a right triangle whose longer leg is 9 mm shorter than the hypotenuse and 4 mm longer than the shorter leg.
  19. Inequation
    inequalities Solve the inequation: 5k - (7k - 1)≤ 2/5 . (5-k)-2
  20. Mr. John
    jabka Mr. John wants to buy winter apples Spartan. There are two ways to buy: 1) buy apples at the marketplace, where 1 kg costs 15 CZK. 2) Bring the car to the agricultural farm, where the apples are sold after 9 CZK per kilogram. However, he must pay CZK 150.

Do you have interesting mathematical example that you can't solve it? Enter it and we can try to solve it.

To this e-mail address we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.