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

#### Number of problems found: 931

• 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.
• Rectangle 45 The perimeter of a rectangle is 60cm. If the length of the rectangle is 20cm. a)find the width b)find the area.
• Diamond diagonals Find the diamond diagonal's lengths if the area is 156 cm2 and side is 13 cm long.
• 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?
• Area to volume If the surface area of a cube is 486, find its volume.
• 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: sin4 θ - 1/cos2 θ=cos2 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 cm2, find the side of the rhombus.
• 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?
• Pilot How high is the airplane's pilot to see 0.001 of Earth's surface?
• 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?
• 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 cm2?
• Isosceles trapezium Calculate the area of an isosceles trapezium ABCD if a = 10cm, b = 5cm, c = 4cm.
• Cylinder height Calculate the height of the cylinder and its surface is 2500 dm2 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?
• Hexagon in circle Calculate the radius of a circle whose length is 10 cm greater than the circumference of a regular hexagon inscribed in this circle.
• 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

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