Grade - examples - page 99

  1. Series
    fib Your task is express the sum of the following arithmetic series for n = 14: S(n) = 11 + 13 + 15 + 17 + ... + 2n+9 + 2n+11
  2. Reciprocal
    complex_numbers Calculate reciprocal of z=0.8+0.6i:
  3. Cookies
    koláčky Mom bake cookies. Rolo took 2/9 of all cookies, Michal 3/9. How many cookies ate Rolo if Michal had 9.
  4. Roof
    roof Tiles are stacked in rows on the trapezoidal shaped roof. At the ridge is 15 tiles and each subsequent row has one more tile than in the previous row. How many tiled is covered roof if lowermost row has 37 tiles?
  5. Basketball
    friends_1 Peter and Franta threw to the basket. Each had 20 attempts. Peter scored thirteen and twelve Franta. Give them success in percentage.
  6. 3 days
    kontrolor Worker checked 2,950 products in 3 days. Second day checked 25% more than the first day. The third day 15% more products than the second day. How many products he checked in each day.
  7. Speedometer
    lotus The speedometer of a car reads 66 km/h. It's accurate to within 4.1% What is the maximum possible error?
  8. Chords
    chords How many 4-tones chords (chord = at the same time sounding different tones) is possible to play within 7 tones?
  9. Water tank
    nadrz Water tank shape of cuboid has dimensions of the bottom 7.5 meters and 3 meters. How high will reach the water in the tank will flow 10 liters of water per second and the inflow will be open 5/6 hour? (Calculate to one decimal place and the results give in
  10. Parallelogram ABCD
    paralleogram_1 The area of parallelogram ABCD is 440 cm2. Points M and N are the midpoints of the sides AB and BC. What is the area of a quadrilateral MBND?
  11. Office
    hranol-6u Office building was built in the shape of a regular hexagon inscribed in a circle with a radius of 12 m. The height of the walls is 7m. How much CZK cost plastering the walls of the building, if per 1 m square cost CZK 400?
  12. Waiting room
    fly In the waiting room are people and flies. Together they have 15 heads and 50 legs (fly has 6 legs). How many people and flies are in the waiting room?
  13. Moivre 2
    moivre_complex Find the cube roots of 125(cos 288° + i sin 288°).
  14. Candelas
    sviecky We burned two unequally thick and long candles. Longer burnt for three and a half hours and shorter for five hours. After two hours of burning it was identical. How many times was longer candle longer then shorter?
  15. Price reduction
    camera Price of camera is 654 USD on sale its price reduced to 411 USD. Calculate the percentage reduction in the price of the camera.
  16. Cube 5
    cubes_10 The content area of one cube wall is 32 square centimeters. Determine the length of its edges, its surface and volume.
  17. Average height
    vyska In a class are 34 students. The average height of students is 165 cm. What will be the average height of students in the classroom when two pupils tall 176 cm and 170 cm moved from this school/class?
  18. Unknown number 5
    seven I think unknown number. If we enlarge it five times then subtract 3 and result decreases by 75% we get the number by one greater than the number I think. What number am I thinking?
  19. Book
    math_book John read the book so that it read 30 pages per day. Maxim read 34 pages a day and read it two days earlier than John. How many pages has the book?
  20. Strange x
    pie For what x is true ??

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