# Expression of a variable from the formula - math word problems

- Two friends

Peter can do all his work himself in 6 hours. Martin can do the same work himself in 8 hours. Peter worked first and then replaced by Martin. Whole work was done in 6.5 hours. Calculate how long Peter worked before replaced by Martin. - Area to volume

If the surface area of a cube is 486, find its volume. - Sugar production

From 1 ton of beet, 150 kg of sugar is produced. To clean 1 ton of sugar 450 kg of lime is consumed. Calculate how many kgs of lime is consumed when processing 1 ton of sugar beet? - Marriage sttus

In our city, there are 3/5 of the women married to 2/3 of the men. Find what part of the population is free. - Calculate 2

Calculate the largest angle of the triangle whose side are 5.2cm, 3.6cm, and 2.1cm - Substitution method

Solve goniometric equation: sin^{4}θ - 1/cos^{2}θ=cos^{2}θ - 2 - Cube

The sum of all cube edges is 30cm. Find the surface area of the cube. - Diagonals of a rhombus 2

One diagonal of a rhombus is greater than other by 4 cm . If the area of the rhombus is 96 cm^{2}, find the side of the rhombus. - Pilot

How high is the airplane's pilot to see 0.001 of Earth's surface? - Isosceles trapezium

Calculate the area of an isosceles trapezium ABCD if a = 10cm, b = 5cm, c = 4cm. - Diagonals of the rhombus

How long are the diagonals e, f in the diamond, if its side is 5 cm long and its area is 20 cm^{2}? - Isosceles trapezoid

The old father decided to change the top plate of an isosceles-like trapezoid with the basic dimensions of 120 cm and 60 cm, and the shoulder is 50 centimeters long. How much does it pay for a new plate and a square meter worth 17 euros? - Hectoliters

How deep is the pool if there are 2025 hectoliters of water and the bottom dimensions are a = 15 meters b = 7,5 meters and the water level is up to 9/10 (nine-tenths) of height. - Three pumps

We are filling the pool. The first pump would be filled in 12 hours, the second pump in 15 hours. If all three pumps were running at the same time, it would fill the pool for 4 hours. How long would the pool fill only with the third pump? - Cylinder height

Calculate the height of the cylinder and its surface is 2500 dm^{2}and the bases have a diameter 5dm. - Boats

Three-quarters of boats are white, 1/7 are blue and 9 are red. How many boats do we have? - Non linear eqs

Solve the system of non-linear equations: 3x^{2}-3x-y=-2 -6x^{2}-x-y=-7 - Symmetry by plane

Determine the coordinates of a image of point A (3, -4, -6) at a symmetry that is determined by the plane x-y-4z-13 = 0 - Rectangle diagonal

The rectangle, one side of which is 5 cm long, is divided by a 13 cm diagonal into two triangles. Calculate the area of one of these triangles in cm^{2}. - Body diagonal

Calculate the cube volume, whose body diagonal size is 75 dm. Draw a picture and highlight the body diagonal.

Do you have an interesting mathematical word problem that you can't solve it? Submit math problem, and we can try to solve it.