Expression of a variable from the formula - math word problems

  1. Equilateral triangle
    equilateral_triangle2_1 Calculate the area of an equilateral triangle with circumference 72cm.
  2. Twenty
    rabbits_1 Twenty rabbits are put in 4 cells so that there are different number of rabbits in each cell contains at least 3 rabbits. What is the largest possible number of rabbits in one cell
  3. Surface of cubes
    cubes3_6 Peter molded a cuboid 2 cm, 4cm, 9cm of plasticine. Then the plasticine split into two parts in a ratio 1:8. From each part made a cube. In what ratio are the surfaces of these cubes?
  4. Diagonal to area
    rectangle_5 Calculate the area of a rectangle in which the length of the diagonal is 10 cm.
  5. The bulbs
    resistor_6 The bulbs are connected serially two bulbs and one resistor. Each bulb has a resistivity of 100 ohms and resistor of 60 ohms The voltage source in the circuit is 24 volts. Do you know what voltage to measure on individual appliances?
  6. Flying
    aircraft-02_8 The airplane from Prague to Bratislava was flying at a speed of 60 km/h less and back by 70 km/h greater than the original speed. What was the original speed if the plane returned to Prague according to the timetable?
  7. Find the 2
    square_4 Find the term independent of x in the expansion of (4x3+1/2x)8
  8. Perimeter of a rectangle
    rectangle_4 If the perimeter of a rectangle is 114 meters and the length is twice the width plus 6 meters, what are the length and width?
  9. Exponential warm
    teplomer_6 Suppose that a body with temperature T1 is placed in surroundings with temperature T0 different from that of T1. The body will either cool or warm to temperature T(t) after time t, in minutes, where T(t)=T0 + (T1-T0)e^(-kt) . If jello salad with 30 degr
  10. Cuboid
    kvader11 The sum of the lengths of the three edges of the cuboid that originate from one vertex is 210 cm. Edge length ratio is 7: 5: 3. Calculate the length of the edges.
  11. Equilateral triangle
    vpisany_stvorec A square is inscribed into an equilateral triangle with a side of 10 cm. Calculate the length of the square side.
  12. Cube edges
    cubes3_3 If the edge length of the cube increases by 50%, how does the volume of this cube increase?
  13. Right triangular prism
    hranol3b We have cuboid with a base and dimensions of 12 cm and 5 cm and height of 4 cm. The tablecloth cut it into two identical triangular prisms with right triangular bases. The surface of the created prisms was painted with color. Calculate the surface area of
  14. The price
    map_16 The price of the land increased by 17%. What was the original price of the land if it now costs 46800 €?
  15. Meat loses
    maso_3 Meat loses 18% of its weight by smoking. How much raw meat butcher used to manufacture 35 kilos of smoked?
  16. Trapezoid - intersection of diagonals
    intersect_trapezoid_diagonals In the ABCD trapezoid is AB = 8 cm long, trapezium height 6 cm, and distance of diagonals intersection from AB is 4 cm. Calculate trapezoid area.
  17. Bread to kilos
    chlieb_3 They brought in d two kilos and t three kilos of bread to the store. By the end of the day, 14 two-kg bread were sold. How many kilos of bread remained in the store by the next day?
  18. Twelve
    stromy_9 Twelve students work on a week forestry brigade. One hundred spruces will receive x CZK, one hundred pine y CZK. How many receive each one students did in one day if they planted a total of 25,000 spruces per week and 30,000 pine trees? Express by express
  19. Sum of squares
    pytagorean The sum of squares above the sides of the rectangular triangle is 900 cm2. Calculate content of square over the triangle's hypotenuse.
  20. The coil
    lano_1 How many ropes (the diameter 8 mm) fit on the coil (threads are wrapped close together) The coil has dimension: the inner diameter 400mm, the outside diameter 800mm and the length of the coil is 470mm

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