# Expression of a variable from formula - examples

- Isosceles trapezoid

Calculate the content of an isosceles trapezoid whose bases are at ratio 5:3, the arm is 6cm long and it is 4cm high. - Wine

A bottle of wine costs 21 euros; and wine is 20 times more expensive than a bottle. How much a bottle cost? - Trench

The trench is a four-sided prism. The cross section has a trapezoidal shape with basements of 4m and 6m, the length of the trench is 30m. What is the depth of the trench if we dig 60,000 l of soil. - Truncated cone 3

The surface of the truncated rotating cone S = 7697 meters square, the substructure diameter is 56m and 42m, determine the height of the tang. - Water channel

The cross section of the water channel is a trapezoid. The width of the bottom is 19.7 m, the water surface width is 28.5 m, the side walls have a slope of 67°30' and 61°15'. Calculate how much water flows through the channel in 5 minutes if the water flow - Regular n-gon

In a regular n-angle polygon the internal angle is 144 degrees. Find the number n indicating the number of sides of this polygon. - Arithmetic progression

In some AP applies: 5a2 + 7a5 = 90 s3 = 12 Find the first member a =? and difference d = ? - Cuboid

Cuboid has a surface of 516 cm^{2.}Side a = 6 cm and b = 12 cm. How long is the side c =? - Surface of cuboid

Find the surface of the cuboid if its volume is 52.8 cm^{3}and the length of its two edges is 2 cm and 6 cm. - Cuboid edges in ratio

Cuboid edges lengths are in ratio 2:4:6. Calculate their lengths if you know that the cuboid volume is 24576 cm^{3.} - Cuboid - volume and areas

The cuboid has a volume of 250 cm^{3,}a surface of 250 cm^{2}and one side 5 cm long. How do I calculate the remaining sides? - Cylinder - h

Cylinder volume is 129 cm^{3.}Base radius is 3 cm. Calculate the height of the cylinder. - Tereza

The cube has area of base 64 mm^{2.}Calculate the edge length, volume and area of its surface. - MO SK/CZ Z9–I–3

John had the ball that rolled into the pool and it swam in the water. Its highest point was 2 cm above the surface. Diameter of circle that marked the water level on the surface of the ball was 8 cm. Determine the diameter of John ball. - Theater

The theater has in each row with 11 seats. Ticket to the first 8 rows is for 198 KČ. In next rows is for 84 KČ. The theater was completely sold out. Revenue was 34980 KČ. How many rows are in the theater? - Garden

Trapezoid garden has parallel sides 21 m and 23 m. Its area is 220 square meters. What is the width of the garden? - Garden

Father dig up the garden in 13 hours. Son in 18 hours. How many hours take dig up the garden together? - Painters

Five painters painting the fence for eight days. How many days over will take work if paint the fence only four decorators? - Similarity of squares

The ratio of the similarity of the squares ABCD and KLMN is 2.5. Square KLMN area is greater than area of a square ABCD with side a: ? - Triangles

Equilateral triangle with side 25 cm has the same perimeter as an isosceles triangle with arm of 32 cm. Calculate the base x of an isosceles triangle.

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