Area of shape + percentages - math problems

Number of examples found: 52

  • Diameters of circles
    circle5_1 How many percent of the area of a larger circle is a smaller circle if the smaller circle has a diameter 120 mm and a larger one has a diameter 300 mm?
  • Square - increased perimeter
    rectangles_4 How many times is increased perimeter of the square, where its sides increases by 150%? If the perimeter of square will increase twice, how much% increases the content area of the square?
  • Pipeline
    pipeline How much percent has changed (reduced) area of pipe cross-section, if circular shape changed to square with same perimeter?
  • Square
    squares_inc If we increase side of the square, increase its area of 63%. What is the percentage we increase side of the square?
  • Cutting circles
    circles2_2 From the square 1 m side we have to cut the circles with a radius of 10 cm. How many discs we cut and how many percent will be waste?
  • Rectangle area
    rectangles_5 The length of a rectangle of x units is increased by 10% and its width of y units is increased by 15%. What is the ratio of the area of the old rectangle to the area if the new rectangle?
  • Hop-garden
    chmelnica The length of the rectangular hop garden Mr. Smith increased by 25% and its width by 30%. What is the percentage change in area of hop garden?
  • Screens
    tv2_3 The area of a 25 inch TV screen is 300 inch² the area of a 40 inch TV screen is 768 inch². The area of the smaller screen is what percent of the area of the larger screen?
  • Content area and percents
    squares_8 Determine what percentage is smaller cube surface, when the surface area of the wall decreases by 25%.
  • Percent change
    rectangles If the length of a rectangle is increased by 25% and the width is decreased by 10%, the area of the rectangle is larger than the area of the original rectangle by what percent?
  • Waste
    doska_kruh How many percents are waste from a circular plate with a radius of 1 m from which we cut a square with the highest area?
  • Seat
    cubes3 How much m² of fabric do we need to sew a 50cm-shaped cube-shaped seat if 10% of the material we add to the folds?
  • A screen
    tv2_5 A screen is 1680 x 1050 pixels. What are the coordinates (and size in pixels) of an centered area which is exactly 33% of the screen size?
  • Cutting square
    circle22 From a square with a side of 30 cm, we cut the circle with the highest possible diameter. How many percents of the square content is this circle?
  • Desribed circle to rectangle
    rectangle_in_circle_1 Rectangle with sides 6 cm and 4 cm was circumscribed circle. What part of the content of the circle determined by the circumscribed circle occupies a rectangle? Express in perctentages(%).
  • Percentage of waste
    14 In a square plate with side 75 cm we cut 4 same circles. Calculate the percentage of waste.
  • Expansion
    magnification If one side of the rectangle is larger 4-times and second 2-times, what percentage increases the area of rectangle?
  • Square side
    squares If we enlarge the square side a = 5m, its area will increase by 10,25%. How many percent will the side of the square increase? How many percent will it increase the circumference of the square?
  • Square metal sheet
    plech_2 Four squares of 300 mm side were cut out from a square sheet metal plate with a side of 0,7 m. Express the fraction and the percentage of waste from the square metal sheet.
  • Percentage and rectangle
    obdelnik2 About what percentage increases perimeter and area of a rectangle if both the sides 12 cm and 10 cm long we increase by 20%?

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