- 9th grade (14y) - math problems

Number of problems found: 3183

  • RT - hypotenuse and altitude
    pravy_trojuholnik Right triangle BTG has hypotenuse g=117 m and altitude to g is 54 m. How long are hypotenuse segments?
  • Chords
    chords How many 4-tones chords (chord = at the same time sounding different tones) is possible to play within 7 tones?
  • Discounts on rail (ZSSK)
    preukazy_zssk The railway company ZSSK offers a discount of 15% (REGIONAL) for 5 Eur/year. Calculate the real discount rate as a percentage, where passengers will travel 19 Eur per week.
  • Confectionery
    cukrovinky The village markets have 5 kinds of sweets, one weighs 31 grams. How many different ways a customer can buy 1.519 kg sweets.
  • Sphere A2V
    sphere3 The surface of the sphere is 241 mm2. What is its volume?
  • Sphere growth
    sphere How many times grow volume of sphere if diameter rises 10×?
  • Football league
    football In the 5th football league is 10 teams. How many ways can be filled first, second and third place?
  • 2nd class variations
    cards From how many elements you can create 2450 variations of the second class?
  • Sphere fall
    sphere How many percent fall volume of a sphere if diameter decreases 3×?
  • Circle arc
    pizza Circle segment has a circumference of 135.26 dm and 2096.58 dm2 area. Calculate the radius of the circle and size of the central angle.
  • Floating barrel
    floating_barrel Barrel (cylinder shape) floats on water, top of the barrel is 8 dm above water, and the width of surfaced barrel part is 23 dm. Barrel length is 24 dm. Calculate the volume of the barrel.
  • 3y inflation
    bread Price of the roll rise in the first year by 9%, the second year fell by 5% and in the third year increased by 3%. Calculate the average annual increase in price of the roll.
  • Inflation
    tsar Once upon a time, tsar owned a money printer and printed and printed. The result of printing money prices went up,in the first year 3.9 %, in the second 6%, in the third 4.7% and in the fourth 5.5%. Then tsar was failed in election. Calculate the average
  • Circles
    three-circles Three circles of radius 95 cm 78 cm and 64 cm is mutually tangent. What is the perimeter of the triangle whose vertices are centers of the circles?
  • Triangle ABC
    ABC Right triangle ABC with right angle at the C, |BC|=18, |AB|=33. Calculate the height of the triangle hAB to the side AB.
  • Two doctors
    dr_cvach Doctor A will determine the correct diagnosis with a probability of 93% and doctor B with a probability of 79%. Calculate the probability of proper diagnosis if both doctors diagnose the patient.
  • Monkey
    monkey The monkey fell in 40 meters deep well. Every day it climbs 3 meters, at night it dropped back by 2 m. On what day it gets out from the well?
  • Clocks
    clocks How will long path walk the end of the clock's minute-hand long 7 cm for 330 minutes? How long will walk in the same time hour-hand?
  • Kites
    drake Boys run kite on a cable of 68 meters long. What is the kite altitude, if the angle from the horizontal plane is 72°?
  • Ladislav in Amsterdam
    jakob3 Laco went (was sent) to a conference in Amsterdam for a reward. The conference fee was € 2536. Calculate how many books Ladislav could buy at the price of 46 and 54 euros if he doesn't want to fill the whole home library, and he can buy only 52 books

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