Expression of a variable from the formula - 7th grade (12y) - math problems

Number of examples found: 209

  • Simple equations
    enc2 Solve system of equations: 5x+3y=5 5x+7y=25
  • Unknown number 24
    numbs_6 f we add 20, we get 50% of its triple. What is this unknown number?
  • Two thirds
    fractions_10 Find two-thirds of the number equal to two-thirds of 99
  • Simple equation 3
    equilateral_triangle_2 24 = n • 27, solve for n
  • Perimeter to area
    circles_1 Calculate the area of a circle with the perimeter 15 meters.
  • Given
    1998-4b Given 2x =0.125 find the value of x
  • Cargo
    tractor_lorry Car with cargo weight 7610 kg. Weight of car is 23% of the total weight of car and cargo. How heavy is cargo?
  • Cube
    cube_diagonals_3 The sum of all cube edges is 30cm. Find the surface area of the cube.
  • Which
    plusminus_11 Which decimals when subtracted equal 3.89: a - b = 3.89
  • Diagonal of square
    ctverec_mo_1 Calculate the side of a square when its diagonal is 10 cm.
  • Area to volume
    two_cubes_2 If the surface area of a cube is 486, find its volume.
  • Third dimension
    star_1 Calculate the third dimension of the cuboid: a) V = 224 m3, a = 7 m, b = 4 m b) V = 216 dm3, a = 9 dm, c = 4 dm
  • Simplify 2
    expr Simplify expression: 5ab-7+3ba-9
  • Interior angles
    triangles_1 Calculate the interior angles of a triangle that are in the ratio 2: 3: 4.
  • The perimeter 3
    rectangles The perimeter of a rectangle is 35 cm. The ratio of the length to its width is 3:2. Calculate the dimensions of the rectangle
  • One and a half chicken
    chicken_1 One and a half chicken bears one and a half egg in one and a half day. How many eggs can withstand from 6 chicken in 6 days?
  • Hotel
    hotel The hotel has a p floors each floor has i rooms from which the third are single and the others are double. Represents the number of beds in hotel.
  • Rhombus A2p
    kosostvorec Rhombus area is 13 cm2 and its height is 5cm long . Determine a perimeter of this rhombus.
  • Cube surface and volume
    cube_shield_6 Find the surface of the cube with a volume of 27 dm3.
  • Cube edges
    cube_shield_3 The sum of the lengths of the cube edges is 42 cm. Calculate the surface of the cube.

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