Examples for 9th grade - page 29

  1. Unknown number
    unknown Unknown number is divisible by exactly three different primes. When we compare these primes in ascending order, the following applies: • Difference first and second prime number is half the difference between the third and second prime numbers. • The produ
  2. Mother and daughter 2
    mother_baby The mother is 40 years older than her daughter. How old is the mother if her age is eight thirds age of daughter?
  3. Football league
    football_1 In the 4th football league plays each of the 16 participants with each opponent twice. For every victory gets 3 points, 1 point for a draw, a defeat none. After the competition was team with 56 points and 8 defeats at 6th place. How many times have won?
  4. Sportsman
    lungs A trained athlete is able to exhale after a deep breath still 500 ml of air. At normal inhalation and exhalation is breathing 500 ml of air. Within one minute, one breath and exhaled 19 times. What part of breathing air per day is one exhalation?
  5. Vectors
    vectors Vector a has coordinates (7; 16) and vector b has coordinates (15; -7). If the vector c = b - a, what is the magnitude of the vector c?
  6. Tachometer
    tatra-dakar2 Tatra's tachometer shows the initial state 154009 km this morning. Tatra today travel at an average speed of 35 km/h. Determine the function that describes the Tatra's tachometer depending on the time. What is the state of tachometer after 4.8 hours?
  7. Combi-triangle
    komb_triangle On each side of the square is marked 2 different points outside the vertices of the square. How many triangles can be constructed from this set of points, where each vertex of the triangle lie on the other side of the square?
  8. Rectangle
    rectangle_inscribed_circle The rectangle is 36 cm long and 48 cm wide. Determine the radius of the circle circumscribing rectangle.
  9. Freedom
    family_life In the city are 2/6 of women married for 4/4 men. What proportion of the townspeople is free (not married)? Express as a decimal number.
  10. Fraction
    polynomial For what x expression ? equals zero?
  11. Felix
    astronaut Calculate how much land saw Felix Baumgartner after jump from 22 km above ground. The radius of the Earth is R = 6378 km.
  12. Heron backlaw
    heron_math Calculate missing side in a triangle with sides 33 and 27 and area 118.3.
  13. The cyclist
    cyclist The cyclist went from village to town. First half of journey went at 19 km/h. The second half of the journey, which mostly fell, went at 33 km/h. All journey took 67 minutes. Calculate the distance from the village to the town.
  14. Dried apples
    jablka_2 How many kilograms of fresh apples id needed to 120 kg of dried apples when from 0.4 tons of fresh apples we get 75 kg of dried apples?
  15. Cancer
    cancer Of the 80 people 50 people ill cancer. What percentage of people isn't ill?
  16. Siblings
    tri-sourozenci Three siblings had saved up a total of 1,274 CZK. Peter had saved up to 15% more than Jirka and Hanka 10% less than Peter. How much money they saved each one of them?
  17. Glass
    sklenice_1 Trader ordered from the manufacturer 200 cut glass. The manufacturer confirmed the order that the glass in boxes sent a kit containing either four or six glasses. Total sent 41 boxes. a) How many boxes will contain only 4 glasses? b) How many boxes will co
  18. Numbers at ratio
    number-2_2 The two numbers are in a ratio 3:2. If we each increase by 5 would be at a ratio of 4:3. What is the sum of original numbers?
  19. AP - simple
    sigma_1 Determine the first nine elements of sequence if a10 = -1 and d = 4
  20. Pedestrian and the cyclist
    cyklista_1 Pedestrian and cyclist went against each from the two cities that are distant 40 km. Pedestrian started 30 minutes before the cyclist and walk an average speed of 5 km/h. What speed went cyclist when met after 120 minutes from the start of the pedestrian?

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.