# Area + percentages - math problems

#### Number of problems found: 94

• Screens 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 Determine what percentage is smaller cube surface, when the surface area of the wall decreases by 25%. Alaska is the largest state in the United States and has a surface area of approximately 588,000 square miles. Montana has a surface area that is approximately 25% of the surface area of Alaska. What is the approximate surface area of Montana?
• Cllub flag The children had the club flag sewn on. The red color covered 2/20 of the total area of the flag, the blue area a fifth, the yellow 19% of the total area. What% is the green area occupied?
• Earth's surface The greater part of the earth's surface (r = 6371 km) is covered by oceans; their area is approximately 71% of the Earth's surface. What is the approximate area of the land?
• Surface area 2 Calculate how many % reduce the surface area of the cube is we reduced length of each edge by 10%.
• The surface area How much percent will the surface area of a 4x5x8 cm block increase if the length of the shortest edge is increased by 2 cm?
• Built-up area John build up area 5 x 7 = 35 m2 with building with a wall thickness 30 cm. How many centimeters would have to subtract from thickness of the walls that built-up area fell by 9%?
• Rectangle area 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?
• Pipeline How much percent has changed (reduced) area of pipe cross-section, if circular shape changed to square with same perimeter?
• Percent change 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?
• Square If we increase side of the square, increase its area of 63%. What is the percentage we increase side of the square?
• Waste 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?
• Expansion If one side of the rectangle is larger 4-times and second 2-times, what percentage increases the area of rectangle?
• A screen 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?
• Percentages Calculate the percentages to two decimal places: a / 15 min in 4 hours B / 35 cm2 of 12.5 dm2 c / 2dm2 of 400 cm2 D / 0.2 liters from 2.2 liters
• Three shapes 1/5 of a circle is shaded. The ratio of area if square to the sum of area of rectangle and that of the circle is 1:2. 60% of the square is shaded and 1/3 of the rectangle is shaded. What is the ratio of the area of circle to that of the rectangle?
• Painting The room is long 50 meters and wide 60dm and 300 cm high. Calculate how much it will cost painting if area of windows and doors is 15% of the total area. One square meter cost 50cents.
• Triangle KLB It is given equilateral triangle ABC. From point L which is the midpoint of the side BC of the triangle it is drwn perpendicular to the side AB. Intersection of perpendicular and the side AB is point K. How many % of the area of the triangle ABC is area o
• Square Suppose the square's sides' length decreases by a 25% decrease in the content area of 28 cm2. Determine the side length of the original square.

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