Expression of a variable from the formula - math word problems

Number of examples found: 808

  • Spherical cap
    gulovy_odsek Place a part of the sphere on a 4.6 cm cylinder so that the surface of this section is 20 cm2. Determine the radius r of the sphere from which the spherical cap was cut.
  • Aquarium height
    akvarko How high does the water in the aquarium reach, if there are 36 liters of water in it? The length of the aquarium is 60 cm and the width is 4 dm.
  • Compound interest 4
    exp_growth2 3600 dollars is placed in an account with an annual interest rate of 9%. How much will be in the account after 25 years, to the nearest cent?
  • Five element
    sequence_geo The geometric sequence is given by quotient q = 1/2 and the sum of the first six members S6 = 63. Find the fifth element a5.
  • Spherical tank
    spherical-tanks The tank of a water tower is a sphere of radius 35ft. If the tank is filled to one quarter of full, what is the height of the water?
  • 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.
  • Cube diagonals
    cube_diagonals_4 Calculate the length of the side and the diagonals of the cube with a volume of 27 cm3.
  • Cube edge
    cubes_9 Determine the edges of the cube when the surface is equal to 37.5 cm square.
  • Determine AP
    diff Determine the difference of the arithmetic progression if a3 = 7, and a4 + a5 = 71
  • Circle's chords
    twochords In the circle there are two chord length 30 and 34 cm. The shorter one is from the center twice than longer chord. Determine the radius of the circle.
  • On the farm
    cows On the farm were housed 70 heads of cattle with food supply for 180 days. After 60 days, 10 head of cattle sold, and for the next 30 days they sold 10 more. How many days is sufficient supply of feed for the remaining cattle?
  • VAT on books
    books_13 The cost of a book in the store is 12.5 euros. How much euros is the VAT of this book? VAT is 10%.
  • Arm-leg
    triangles2 Calculate the length of the base of an isosceles triangle with a circumference 224 cm if the arm length is 68 cm.
  • Playground
    playground_fencing Rectangular playground is fenced with 38 m long netting. Its width is 7 m. Calculate its length.
  • A plasticine
    cubes3 Jožko modeled from plasticine. He used 27g of plasticine to model a 3 cm long cube. How many grams of plasticine will it need to mold cubes with an edge of 6cm?
  • Square
    ctverec_1 Danov's father has a square of 65.25 milligram square of wire with a diagonal. How will the square be big when one mm weighs 7 mg?
  • The car
    cars_4 The car has traveled the distance between A and B for four hour. If we increased the average by 17 km/h the car travel this distance an hour earlier. Determine the initial speed of the car and the distance between A and B.
  • Square
    percent If the length of the sides of the square we decrease by 25% decrease the content area of 28 cm2. Determine the side length of the original square.
  • Prism
    prism The volume of tetrahedral prism is 2.43 m3. Base of prism is a parallelogram in which a side 2,5dm and height ha = 18cm. Calculate the height of the prism.
  • Inscribed circle
    inscribed_circle XYZ is right triangle with right angle at the vertex X that has inscribed circle with a radius 5 cm. Determine area of the triangle XYZ if XZ = 14 cm.

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