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

#### Number of problems found: 931

• Trapezium bases
Find the trapezium height if a = 8 cm and c = 4 cm if its content 21 square centimeters.
• Wall diagonal
Calculate the length of wall diagonal of the cube whose surface is 384 cm square.
• Two machines
Performances of two machines are in a ratio of 7:12. A machine with less power produced 406 pieces of products per shift. a) How many pieces produced per shift second machine? b) How many pieces produced two machines together for five shifts?
• Orchard
3/5 of the trees in the orchard are apples, 1/3 are cherries and the remaining five trees are pear. How many trees are in the orchard?
• Bicycle gears
The toothed wheel on the bicycle pedal has 40 teeth, the wheel on the rear wheel has only 16 teeth. How many times does the rear wheel turn if the pedals rotate 50 times?
• Square and rectangle
Calculate the side of a square which content area equals area of the rectangle having a length of 3 cm greater and by 2 cm smaller than the side of the square.
• Angle in RT
Determine the size of the smallest internal angle of a right triangle whose sides constitutes sizes consecutive members of arithmetic progressions.
• Square s3
Calculate the diagonal of the square, where its area is 0.49 cm square. And also calculate its circumference.
• Area of a cube
Calculate the surface area of a cube if its volume is equal to 729 cubic meters.
• Glass
How many glass are needed to produce glass with base regular 5-gon if one base triangle in the base is 4.2 square cm and the height is 10 cm?
• Diagonal of the rectangle
Calculate the diagonal of the rectangle which area is 54 centimeters square and the circuit is equal to 30 cm.
• Cuboid enlargement
By how many percent increases the volume of cuboid if its every dimension increases by 30%?
• Third member
Determine the third member of the AP if a4=93, d=7.5.
• Cube edge
Determine the edges of the cube when the surface is equal to 37.5 cm square.
• Cube 5
The content area of one cube wall is 32 square centimeters. Determine the length of its edges, its surface and volume.
• Unknown number 7
16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
• Three children
3 children eat 8 chocolates in 6 days. How many chocolates 6 children eat in 18 days?
• Raspberries
Dano had 20 raspberries. John had 90% more raspberries than Dano. Determine how many raspberries have Dano and Juraj together.
• Unknown number 5
Daniel think an integer. When he change this number at a ratio of 2:5 he got number 2.8. Determine what number think Daniel.
• Rectangle
Perimeter of rectangle is 48 cm. Calculate its dimensions if they are in the ratio 5:3 (width:height)

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