# The most difficult problems

#### Number of problems found: 7334

• Calculate 3 Calculate the cube volume whose edge is 3x-1,3x-1,3x-1
• Simplify Simplify expression - which expression is equivalent to: 3(m + 2) − 4(2m − 9)
• Rectangular field A rectangular field has a diagonal of length 169m. If the length and width are in the ratio 12:5. Find the dimensions of the field, the perimeter of the field and the area of the field.
• Inquality Solve inequality: 3x + 6 > 14
• One trapezium One trapezium has AB=24M, BC=36M, CD=80M, DA=80M long sides. Find the area.
• Infinite sum of areas Above the height of the equilateral triangle ABC is constructed an equilateral triangle A1, B1, C1, of the height of the equilateral triangle built A2, B2, C2, and so on. The procedure is repeated continuously. What is the total sum of the areas of all tr
• Iron density Calculate the weight of a 2 m long rail pipe with an internal diameter of 10 cm and a wall thickness of 3 mm. The iron density is p = 7.8 g/cm3.
• Perfect cubes Suppose a number is chosen at random from the set (0,1,2,3,. .. ,202). What is the probability that the number is a perfect cube?
• Recipe A recipe requires 2 pounds of flour. If a chef wants to triple the recipe, how many ounces of flour will be needed?
• Flooring a room Find the cost of flooring a room 6.5 m by 5 m with square tiles of sides 25 cm at the rate of rupees 9.40 per tile.
• A tile A tile setter is covering 5ft by 5ft square shower wall. Each tile covers 4 5/8in by 4 5/8in square. How many rows of tile are needed to reach 5ft? How many tiles are needed to cover 5ft by 5ft square
• Find sales tax What is 8.25% sales tax out of 1607.00?
• Non linear eqs Solve the system of non-linear equations: 3x2-3x-y=-2 -6x2-x-y=-7
• Std-deviation Calculate standard deviation for file: 63,65,68,69,69,72,75,76,77,79,79,80,82,83,84,88,90
• A car A car weighing 1.05 tonnes driving at the maximum allowed speed in the village (50 km/h) hit a solid concrete bulkhead. Calculate height would have to fall on the concrete surface to make the impact intensity the same as in the first case!
• Bob traveled Bob traveled 20 meters to Dave's house. He arrived in 3 minutes. What was his average speed for the trip.
• The aquarium The aquarium has a capacity of 18 liters. What is its height when the square bottom is 8 2/3 cm long?
• Right 24 Right isosceles triangle has an altitude x drawn from the right angle to the hypotenuse dividing it into 2 unequal segments. The length of one segment is 5 cm. What is the area of the triangle? Thank you.
• Write 2 Write 791 thousandths as fraction in expanded form.
• Powers 3 2 to the power of n divided by 4 to the power of -3 equal 4. What is the vaule of n?

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