Ratio + unit conversion - math problems

On solving problems and tasks with proportionally, we recommend hint rule of three. Rule of three (proportionality) help solve examples of direct and inverse proportionality. Three members make possible to calculate the fourth - unknown member.

Number of problems found: 63

  • Coke and coal
    coal 20.1 tons of coke is produced from 30 tons of black coal. How much coke is made from 1 kilogram of coal?
  • Vertical rod
    shadow The vertical one meter long rod casts a shadow 150 cm long. Calculate the height of a column whose shadow is 36 m long at the same time.
  • Gears
    bicycle_gears_2 The front gear on the bike has 32 teeth and the rear, on the wheel, has 12 teeth. How many times does the rear wheel of the bike turns if you turn the right pedal 30 times? What distance will you go if the circumference of the bicycle wheel is 250 cm?
  • Sphere in cone
    sphere_in_cone A sphere is inscribed in the cone (the intersection of their boundaries consists of a circle and one point). The ratio of the surface of the ball and the contents of the base is 4: 3. A plane passing through the axis of a cone cuts the cone in an isoscele
  • Chimney and tree
    shadow Calculate the height of the factory chimney, which casts a shadow 6.5 m long in the afternoon. At the same time, a 6 m high tree standing near it casts a shadow 25 dm long.
  • On the
    aircraft-02 On the map of Europe made at a scale of 1: 4000000, the distance between Bratislava and Paris is 28 cm. At what time an airplane flying at 800 km/h will fly this journey?
  • Garden exchange
    land The garden has the shape of a rectangular trapezoid, the bases of which have dimensions of 60 m and 30 m and a vertical arm of 40 m. The owner exchanged this garden for a parallelogram, the area of which is 7/9 of the area of a trapezoidal garden. What is
  • Nutballs
    oriesky The dough for nutballs contains, among other things, two basic raw materials: flour and nuts in a ratio of 2:1. How much flour and how many nuts are needed for 1 kg of dough if "other" is 100g?
  • Squares ratio
    squares2 The first square has a side length of a = 6 cm. The second square has a circumference of 6 dm. Calculate the proportions of the perimeters and the proportions of the contents of these squares? (Write the ratio in the basic form). (Perimeter = 4 * a, conte
  • Cheetah vs antelope
    motion2 When the cheetah began chasing the antelope, the distance between them was 120 meters. Although the antelope was running at 72km/h, the cheetah caught up with it in 12 seconds. What speed was the cheetah running?
  • Two villages
    mapa On the map with a scale of 1:40000 are drawn two villages actually 16 km away. What is their distance on the map?
  • Geometric plan
    map_1 At what scale the building plan if one side of the building is 45m long and 12mm long on a plan?
  • Seawater
    ice_cubes Seawater has a density of 1025 kg/m3, ice 920 kg/m3. 8 liters of seawater froze and created a cube. Calculate the size of the cube edge.
  • SSA and geometry
    ssu_veta The distance between the points P and Q was 356 m measured in the terrain. The PQ line can be seen from the viewer at a viewing angle of 107° 22 '. The observer's distance from P is 271 m. Determine the viewing angle of P and observer.
  • Scale of plan
    zahrada_4 On the plan of the village in the scale of 1: 1000 a rectangular garden is drawn. Its dimensions on the plan are 25mm and 28mm. Determine the area of the garden in ares.
  • Two brothers
    mapa_ta3_3 The two brothers were to be divided according to the will of land at an area of 1ha 86a 30m2 in a ratio of 5:4. How many will everyone get?
  • Scale of the map
    city_5 The distance between two cities is actually 30 km and the map is 6 cm. What is the scale of the map?
  • Sugar 9
    cukr_6 150 kg of sugar beet yields 24 kg of sugar. From how many tons of sugar beet can be obtained three tons of sugar?
  • Cooling liquid
    chladici Cooling liquid is diluted with water in a ratio of 3:2 (3 parts by volume of coolant with 2 volumes of water). How many volumes of coolant must be prepared for a total 0.7 dm3 (liters) of the mixture?
  • Photo egative
    negativ Negative dimensions are 36mm and 28mm. What will be the photo size in the 21:4 ratio?

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