Functions + expression of a variable from the formula - math problems

Number of problems found: 292

  • The notebook
    notes After rising by 40%, the notebook cost 10.50 euros. How much did this notebook cost if it increased in price by only 20% instead of 40%?
  • Annual growth
    exp_growth2 The population has grown from 25,000 to 33,600 in 10 years. Calculate what was the average annual population growth in%?
  • Harmonic mean
    means_math If x, y, z form a harmonic progression, then y is the harmonic mean of x and z. Find the harmonic mean of the numbers 6 and 5.
  • Cuboid edges
    cuboid_3colors The lengths of the cuboid edges are in the ratio 2: 3: 4. Find their length if you know that the surface of the cuboid is 468 m2.
  • Three groups
    workers In the company, employees are divided into three groups. In the first group, which includes 12% of the company's total number of employees, the average salary is CZK 40,000, in the second group CZK 35,000, in the third group CZK 25,000. The average salary
  • Sphere cut
    odsek_gule A sphere segment is cut off from a sphere k with radius r = 1. The volume of the sphere inscribed in this segment is equal to 1/6 of the segment's volume. What is the distance of the cutting plane from the center of the sphere?
  • Railway embankment
    rr_lichobeznik The railway embankment section is an isosceles trapezoid, the sizes of the bases of which are in the ratio 5: 3. The arms have a length of 5 m, and the height of the embankment is 4.8 m. Calculates the size of the embankment section area.
  • Decibel
    tv By what percentage does the sound intensity increase if the sound intensity level increases by 1 dB?
  • 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.
  • The string
    string They cut 113 cm from the string and divided the rest in a ratio of 5: 6.5: 8: 9.5. The longest part measured 38 cm. Find the original length of the string.
  • 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
  • Integer sides
    rt_triangle A right triangle with an integer length of two sides has one leg √11 long. How much is its longest side?
  • Equilateral cone
    kuzel_rs We pour so much water into a container that has the shape of an equilateral cone, the base of which has a radius r = 6 cm, that one-third of the volume of the cone is filled. How high will the water reach if we turn the cone upside down?
  • Powerplant chimney
    komin2 From the building window at the height of 7.5 m, we can see the top of the factory chimney at an altitude angle of 76° 30 ′. We can see the chimney base from the same place at a depth angle of 5° 50 ′. How tall is the chimney?
  • Coins
    mince The money - coins are minted from the hardest bronze, which contains copper and tin in a ratio of 41: 9. How much copper and tin are in 2kg of bronze money?
  • Chord of triangle
    triangle If the whole chord of the triangle is 14.4 cm long, how do you calculate the shorter and longer part?
  • Coils of transformer
    transformator The primary coil of the transformer has 400 turns, a current of 1.5 A passes through it and is connected to a voltage of 220 V. For the secondary coil, find the voltage, current, and a number of turns if the transformation ratio k = 0.1.
  • Dodecagon
    clocks Calculate the size of the smaller of the angles determined by lines A1 A4 and A2 A10 in the regular dodecagon A1A2A3. .. A12. Express the result in degrees.
  • Twice of radius
    gule How many times does the surface of a sphere decrease if we reduce its radius twice?
  • Lookout tower
    tower How high is the lookout tower? If each step was 3 cm lower, 60 more of them were on the lookout tower. If it were 3 cm higher again, it would be 40 less than it is now.

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Functions - math problems. Expression of a variable from the formula - math problems.