# The most difficult examples - page 2

- ICE train

German runways test a new ICE train between Munich and Berlin. The train runs to Berlin at a slow speed of 100 km/h. Back from Berlin goes faster. How quickly did the train have to go on a return trip so that the total average train speed for both journeys - Volume of cube

Solve the volume of a cube with width 26cm . - Algebrogram

Solve algebrogram for sum of three numbers: BEK KEMR SOMR ________ HERCI - Triangle

Determine whether a triangle can be formed with the given side lengths. If so, use Heron's formula to find the area of the triangle. a = 158 b = 185 c = 201 - ABCD

AC= 40cm , angle DAB=38 , angle DCB=58 , angle DBC=90 , DB is perpendicular on AC , find BD and AD - Billiard balls

A layer of ivory billiard balls of radius 6.35 cm is in the form of a square. The balls are arranged so that each ball is tangent to every one adjacent to it. In the spaces between sets of 4 adjacent balls other balls rest, equal in size to the original. T - EQ2

Solve quadratic equation: ? - Fe vs. H2O

The volume of what the body of the same weight is greater - iron or water? - Brackets 2

Add parenthesis to make true: 5-2×6-4+2=5 - Triangle ABC v2

Area of the triangle is 12 cm square. Angle ACB = 30º , AC = (x + 2) cm, BC = x cm. Calculate the value of x. - Prism bases

Volume perpendicular quadrilateral prism is 360 cm^{3}. The edges of the base and height of the prism are in the ratio 5:4:2 Determine the area of the base and walls of the prism. - Notebooks

Liza a store owner buys 560 notebooks. He sold 3/8 of the notebook then she adds the stocks of notebook of 1/4 of the number of notebooks she bought. What is the total number of notebook she bought? - Property

The length of the rectangle-shaped property is 8 meters less than three times of the width. If we increase the width 5% of a length and lendth reduce by 14% of the width it will increase the property perimeter by 13 meters. How much will the property cost - Plane II

A plane flew 50 km on a bearing 63degrees20 and the flew on a bearing 153degrees20 for 140km. Find the distance between the starting point and the ending point - Simple equation 3

24 = n • 27, solve for n - Diagonals in the diamond

The length of one diagonal in diamond is 24 cm greater than the length of the second diagonal and diamond area is 50 m^{2}. Determine the sizes of the diagonals. - Shade

Shade the area on the grid that shows 5/8 x 2/4 - Friends

James and Jaroslav are friends. Together they had 48 toy cars. But if John took 8 cars from Jaroslav, Jaroslav will be have 1.5 times more toy cars than James. How many toy cars had Jaroslav and James? - Tiles

How much you will pay CZK for laying tiles in a square room with a diagonal of 8 m if 1 m^{2}cost CZK 420? - Carpet

The room is 10 x 5 meters. You have the role of carpet width of 1 meter. Make rectangular cut of roll that piece of carpet will be longest possible and it fit into the room. How long is a piece of carpet? Note .: carpet will not be parallel with the diag

Do you have an interesting mathematical example that you can't solve it? Enter it, and we can try to solve it.