Examples for 9th grade - page 15

  1. Heron backlaw
    heron_math Calculate missing side in a triangle with sides 33 and 27 and area 118.3.
  2. Pairs
    pair At the table sit 12 people, 6 on one side and 6 on the other side. Among them are 5 pairs. Every pair wants to sit opposite each other. How many ways can they sit?
  3. EQL triangle
    rs_triangle Calculate inradius and circumradius of equilateral triangle with side a=100 cm.
  4. Morse alphabet
    morse_code Calculate how many words of Morse code to create compiling commas and dots in the words of one to five characters.
  5. Wheat
    field_1 The rectangle shaped field with dimensions 979 m and 540 m harvested last year was 2775 q wheat. (1 q = 1 quintal = 100 kg). During the year, it was necessary to fix the pipe and therefore did kick wide 6 m parallel to the side of the field 540 m, where no
  6. Compass
    wind_rose What angle are between directions W (West) and SE (SouthEast) on the compass?
  7. Steamship
    parnik Between the two ports on the river is going steamship. The journey there and back takes 14:49. Downstream steamship traveling at 21 km/h, upstream 9 km/h. What is the distance between the ports?
  8. Scrap
    chair_bad From 8 products are 2 scrap. What is the probability that the random pick of 2 products have no defective product?
  9. Parallelogram
    paralleogram Calculate area of the parallelogram ABCD as shown if |AB| = 45 cm, |BC| = 23 cm and angle BAD = 30°
  10. Cone and the ratio
    kuzel Rotational cone has a height 28 cm and the ratio of the base surface to lateral surface is 4: 7. Calculate a surface of the base and the lateral surface.
  11. Blueberries
    boruvky Marie earns 1.8 liters of blueberries for 1.2 hours, Peter 2.6 liters for 1.2 hours. How long have earns together one liter?
  12. Accidents
    nehoda-pomnik The count of accidents in 1993 caused 8009 women which is 7.1%. How many men caused the accidents?
  13. Tea blend
    teas Tea blends are maked from two kinds of tea. In standard tea mixture are two teas in the ratio 1:3 and 40 g costs 42 CZK. In the premium tea mixture are weighing two teas in the ratio 1:1 and 50 grams costs 60 CZK. How much cost 10 grams of more expensive k
  14. Vector
    some_vector Calculate length of the vector v⃗ = (-2.5, 6.25, -4.25).
  15. Coin and die
    die Flip a coin and then roll a six-sided die. How many possible combinations are there?
  16. Truncated cone
    kuzel_komoly Calculate the height of the rotating truncated cone with volume V = 1299 cm3 and a base radii r1 = 6.3 cm and r2 = 9.7 cm.
  17. Drunk man
    drunk-man Drunkman has 2.1‰ of alcohol in the blood. How many grams of alcohol has in blood, if he have 6 kg of blood?
  18. Leveling
    quattro Calculate how many 25 kg bags of leveling concrete must be purchased if we leveling room 28 m2 to the "height" 12 mm if consumtion is 1.7 kg per square meter and millimeter thickness.
  19. Right triangle
    right_triangles Calculate the missing side b and interior angles, perimeter and area of ​​a right triangle if a=10 cm and hypotenuse c = 16 cm.
  20. Three workers
    three_workers Three workers A, B, C have to work on a specific task. Workers A and B completed whole task in 25 days, B together with C for 16 days, A together with C for 10 days. How long it would take to complete the task every one of them alone? How long it would.

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