Examples for 9th grade

Number of problems found: 2612

  • Solutions
    bilde How much 60% solution and how much 35% solution is needed to create 100 l of 40% solution?
  • Cone
    r_h_cone Calculate the volume of the rotating cone with a base radius 26.3 cm and a side 38.4 cm long.
  • Cuboid - edges
    kvader_abc The cuboid has dimensions in ratio 4: 3: 5, the shortest edge is 12 cm long. Find: (A) the lengths of the remaining edges, (B) the surface of the cuboid, (C) the volume of the cuboid
  • Two months
    mars with moons Mars has two months, Phobos and Deimos. Phobos orbits around Mars in 7 hours 39 minutes and Deimos in 30 h 14 min. How long will repeat the relative position of the three celestial bodies?
  • A three-digit numbers
    clocks_1 Determine the total number of positive three-digit numbers that contain a digit 6.
  • Pedestrian
    pedestrian Pedestrian came started at 8h in the morning with speed 4.4 km/h. At half-past eleven cyclist started at 26 km/h same way. How many minutes take cyclist to catch up pedestrian?
  • Saving
    cars Allen save € 2860 to buy a car. Yet it lacks save 55% of the car price. How much is the car?
  • Trapezoid
    hexphitri Area of trapezoid is 135 cm2. Sides a, c and height h are in a ratio 6:4:3. How long are a,c and h? Make calculation...
  • Diamond ABCD
    kosoctverec2 In the diamond ABCD is the diagonal e = 24 cm and size of angle SAB is 28 degrees, where S is the intersection of the diagonals. Calculate the circumference of the diamond.
  • Tractors
    tractor_2 Six tractors plowing the field for 8 days. After two days, two tractors broke down. How many days were prolonged work in the field?
  • Right angled triangle 2
    vertex_triangle_right LMN is a right angled triangle with vertices at L(1,3), M(3,5) and N(6,n). Given angle LMN is 90° find n
  • Parcel
    land_parcel Both dimensions of the rectangular parcel were increased by 26%. By how many % has increased its acreage?
  • Two runners
    sprinters_1 Two runners ran simultaneously towards each other from locations distant 34.6 km. The average speed of the first runner was 1/5 higher than the average speed of the second runner. How long should each ran a 34.6 km, if you know that they meet after 67 min
  • Truck PRG-BA
    kamionka Truck driving on highway from Prague to Bratislava at average speed of 72 km/h. At the moment when the truck passes 54 kilometer from Prague passenger car departs from Prague which travel to Bratislava at speed 90 km/h. When and where (at waht highway kil
  • Mushrooms
    huby Fresh mushrooms contain 94% water, dried 14%. How many kg of fresh mushrooms is needed to collect to get 10 kg dried?
  • Points on circle
    coordinates_circle In the Cartesian coordinate system with the origin O is a sketched circle k /O; r=2 cm/. Write all the points that lie on a circle k and whose coordinates are integers. Write all the points that lie on the circle I / O; r=5 cm / and whose coordinates are
  • Again saw
    rectangle_in_circle From the trunk of the tree we have to a sculpture beam with rectangular cross-section with dimensions 146 mm and 128 mm. What is the trunk smallest diameter?
  • Balls
    kulicky Michal said to Martin: give me one ball and I'll have twice as you. Martin said: give me 4 and we will have equally. How many balls each have?
  • Earth's diameter
    om5960-v2 The Earth's diameter on the equator is approximately 12750 km. How long does the Gripen flyover the Earth above the equator at 10 km if it is at an average speed of 1500 km / h?
  • Triangle TBC
    isosceles_triangle TBC is isosceles triangle with base TB with base angle 63° and legs length |TC| = |BC| = 25. How long is the base TB?

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