The most difficult problems
- A photograph
A photograph will stick to a white square letter with a x cm length. The photo is 3/4 x cm long and 20 cm wide than the width of the paper. The surface of the remaining paper surrounding the photograph is 990 cm². Find the size of paper and photo.
- Calculate 8354
In a regular pyramid in which the edge of the base is | AB | = 4cm; height = 6cm, calculate the angle of the lines AV and CV, V = vertex.
- Three-walled 8272
I have only entered the height of a regular three-walled pyramid h = 10 cm. How do I calculate the page length?
- Wheel turns
The diameter of the motorcycle wheel is 55 cm. How many times does a motorcycle wheel turn on a 5 km long road?
- The difference
The difference of two numbers is 1375. If their exact quotient is 12. Find the two numbers
- Hexagon 8167
How many dm² of organic glass is needed to produce 50 washers in the shape of a regular hexagon? The side is 8 cm long.
- Calculate 8166
Calculate the perimeter of a square when we know the length of its diagonal e = 4.2 m
- Three gardens
Is it possible to divide a plot of land with an area of 920 m² into three gardens in a ratio of 4: 2: 3 so that their areas are only whole multiples of square meters?
- Quadrilateral 8120
Include the side edge length of a regular quadrilateral pyramid if the pyramid height is 4 cm and the base area is 16 cm².
- Quadrilateral 8109
The regular quadrilateral pyramid has a base diagonal of 5√2 cm, and the side edges are 12√2 cm long. Calculate the height of the pyramid and its surface.
- Cents-diameter 8084
In what proportion are the diameters of these coins: 10 cents-diameter 19.75mm 20 cents-diameter 22.25mm 50 cents-diameter 24.25mm
- Pile of sand
A large pile of sand has been dumped into a conical pile in a warehouse. The slant height of the pile is 20 feet. The diameter of the base of the sandpile is 31 feet. Find the volume of the pile of sand.
- 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?
- Equilibrium 7990
At the end of one arm of the equilibrium scales, which are in equilibrium, a lead body with a volume V1 is suspended in the air. At the end of the other arm is an aluminum body with a volume V2. The balance arms have sizes l1 and l2, lead density h1 = 11,
- Hyperbola equation
Find the hyperbola equation with the center of S [0; 0], passing through the points: A [5; 3] B [8; -10]
- Coordinates of square vertices
The ABCD square has the center S [−3, −2] and the vertex A [1, −3]. Find the coordinates of the other vertices of the square.
- Rotating 7947
In the rotating cone = 100π S rotating cone = 90π v =? r =?
- Isosceles 7929
ABCD isosceles trapezoid. A = 6cm, e = 7cm and delta angle = 105 °. Calculate the remaining pages.
- Closed drum
Find the total surface area of a closed cylindrical drum if it's diameter is 50 cm and height is 45 cm. (π= 3.14)
- A metal
A metal cylinder is inserted into the cube with a 20 cm edge so that the cylinder shell and its two bases are in close contact with the walls of the cube from the inside. How much water could be poured into the free space between the cube and the cylinder