# The most difficult problems

#### Number of problems found: 6044

• Right triangle from axes A line segment has its ends on the coordinate axes and forms with them a triangle of area equal to 36 square units. The segment passes through the point ( 5,2). What is the slope of the line segment?
• Reciprocal equation 2 Solve this equation: x + 5/x - 6 = 4/11
• Prime factors Write 98 as product of prime factors
• Isosceles Isosceles trapezium ABCD ABC = 12 angle ABC = 40 ° b=6. Calculate the circumference and area.
• Rectangles How many different rectangles with sides integers (in mm) have a circumference exactly 1000 cm? (a rectangle with sides of 50cm and 450cm is considered to be the same as a rectangle with sides of 450cm and 50cm)
• Square into three rectangles Divide the square with a side length of 12 cm into three rectangles with have the same circumference so that these circumferences are as small as possible.
• Right triangle Calculate the length of the remaining two sides and the angles in the rectangular triangle ABC if a = 10 cm, angle alpha = 18°40'.
• Sandbox Sandbox has area of 32 sq ft and length of 4 1/2 ft. What is width of sandbox.
• Digits Show that if x, y, z are 3 consecutive nonzero digits, zyx-xyz = 198, where zyx and xyz are three-digit numbers created from x, y, z.
• Geometric progression 4 8,4√2,4,2√2
• Algebra X+y=5, find xy (find the product of x and y if x+y = 5)
• Simplify 3 Simplify mixed numerals expression: 8 1/4- 3 2/5 - (2 1/3 - 1/4) Show your solution. 3 3/4 + 2 3/5 + 5 1/2 Show your solution. The cone-shaped lampshade has a diameter of 30 cm and a height of 10 cm. How many cm2 of material will we need when we 10% is waste?
• 15 teachers 15 teachers teach for a combined amount of 128 days over a period of 64 days. What is this expressed as a percentage?
• Rectangles The perimeter of a rectangle is 90 m. Divide it into three rectangles, the shorter side has all three rectangles the same, their longer sides are three consecutive natural numbers. What is the dimensions of each rectangle?
• A man A man spends 5/9 of his money on rent, and 5/16 of the remainder on electricity. If the final balance remaining is 550 find how much was spent on rent
• Cube, cuboid, and sphere Volumes of a cube and a cuboid are in ratio 3: 2. Volumes of sphere and cuboid are in ratio 1: 3. At what rate are the volumes of cube, cuboid, and sphere?
• Evaluation of expressions If a2-3a+1=0, find (i)a2+1/a2 (ii) a3+1/a3
• Taxi A taxi ride costs \$3 plus \$2.50 per mile. Write and Graph an equation in two variables that represents the total cost of a taxi ride.

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