Expression of a variable from the formula - math word problems

  1. Average speed
    bus27_4 When the bus stops at bus stops driving average speed is 45 km/h. If it did not stop it drive at speed 54 km/h. How many minutes of every hour it spend at stops?
  2. Diagonals of a rhombus
    rhombus-diagonals_1 One of the diagonals of a rhombus is twice as the other. If the sum of the lengths of the diagonals is 24, find the area of the rhombus.
  3. Body diagonal
    kvader11_1 The cuboid has a volume of 32 cm3. Its side surface area is double as one of the square bases. What is the length of the body diagonal?
  4. Right triangle eq2
    rt_2 Hypotenuse of a right triangle is 9 cm longer than one leg and 8 cm longer than the second leg. Determine the circumference and area of a triangle.
  5. Cube and sphere
    gule_1 Cube with the surface area 150 cm2 is described sphere. What is sphere surface?
  6. Diagonal of square
    ctverec_mo_1 Calculate the side of a square when its diagonal is 10 cm.
  7. Family
    family_5 Son is 3/5 smaller than the mother. Mother is 99 cm higher than the son. How tall is the mother?
  8. Apples 2
    jablka_6 Dried apples contain 15% water. Fresh apples contain 80% water. How many kg of apples we need buy in order to get 3 kg of dried apples?
  9. Rhombus and diagonals
    kosostvorec_2 The a rhombus area is 150 cm2 and the ratio of the diagonals is 3:4. Calculate the length of its height.
  10. Fuel economy
    car1_4 How many kilometers is sufficient petrol in the cylinder fuel tank with a diameter 40 cm and the base of tank length 1 m, when it is filled to 60% and if the car consume 15 liters per 100 km?
  11. Square vs rectangle
    ctverec Square and rectangle have the same area contents. The length of the rectangle is 9 greater and width 6 less than side of the square. Calculate the side of a square.
  12. Two trucks
    cars_6 Two trucks left cities A and B against each other and met after an hour. The first car came to B 27 minutes later than the second car to A. Calculate the car speed if the distance between cities A, B is 90 km.
  13. Combinations
    kvadrat_3 If the number of elements increase by 3, it increases the number of combinations of the second class of these elements 5 times. How many are the elements?
  14. Two cyclists
    compass_1 Two cyclists started from crossing in the same time. One goes to the north speed 20 km/h, the second eastward at speed 26 km/h. What will be the direct distance cycling 30 minutes from the start?
  15. Two diagonals
    rhombus-diagonals The rhombus has a side length 12 cm and length of one diagonal 21 cm. What is the length of the second diagonal?
  16. Cuboid - ratios
    kvader11 The sizes of the edges of the cuboid are in the ratio 2: 3: 5. The smallest wall have area 54 cm2. Calculate the surface area and volume of this cuboid.
  17. Hypotenuse
    RightTriangleMidpoint_1 Calculate the length of the hypotenuse of a right triangle if the length of one leg is 4 cm and its content area is 16 square centimeters.
  18. Rectangle diagonals
    rectangle_diagonals_1 It is given rectangle with area 24 cm2 a circumference 20 cm. The length of one side is 2 cm larger than length of second side. Calculate the length of the diagonal. Length and width are yet expressed in natural numbers.
  19. Diagonals
    koso_uhlopricky Given a rhombus ABCD with a diagonalsl length of 8 cm and 12 cm. Calculate the side length and content of the rhombus.
  20. MO-Z5-3-66 tiles
    stvorce The picture shows a square tiles with side 10 dm which is composed of four identical small rectangles and squares. Circumference of small square is five times smaller than the circumference of the entire tile. Determine the dimensions of the rectangle.

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