# Expression of a variable from formula - examples - page 11

- Rectangle

The rectangle has a perimeter 75 cm. Diagonal length is 32.5 cm. Determine the length of the sides. - Rotary bodies

The rotating cone and the rotary cylinder have the same volume 180 cm^{3}and the same height v = 15 cm. Which of these two bodies has a larger surface area? - Expressions

Expression (3a-7).(3a+7) is identical with: ? - Cylinder twice

If the radius of the cylinder increases twice, and the height is reduced twice, then the volume of the cylinder increases (how many times?): - Jam

Jar with jam weighs 800 grams. Jam weighs three times as much as the empty glass. What is the weight of jam that is in the glass? - Cuboid and ratio

Cuboid has dimensions in ratio 1:2:6 and the surface area of the cuboid is 1000 dm^{2}. Calculate the volume of the cuboid. - Unknown number 7

16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number. - Bus lines

Buses connections are started from bus stop on its regular circuit as follows: No. 27 bus every 27 minutes and No.18 every half hour. What time started this two bus lines run if the bus stop met at 10:15 am.? - Billboard

Rectangular billboard is 2.5 m long with a diagonal 2.8 m long. Calculate the perimeter and the content area of the billboard. - Even / odd numbers

a / Using variable n write two consecutive odd numbers. b / the sum of three consecutive odd numbers is 333. What are this numbers? - Sides ratio

Calculate the circumference of a triangle with area 84 cm^{2}if a:b:c = 10:17:21 - Hollow sphere

The volume of the hollow ball is 3432 cm^{3}. What is its internal radius when the wall thickness is 3 cm? - 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. - Points on circle

In the Cartesian coordinate system with the origin O is a sketched circle k /O; r=2 cm/. Write all the points that lie on a circle k and whose coordinates are integers. Write all the points that lie on the circle I / O; r=5 cm / and whose coordinates are i - Car consumption

The car has passed 988 kilometers and consumed 66 liters of petrol. What is the consumption per 100 kilometers? - Perimeter from area

What is the perimeter of the square if its content is 64 cm^{2}? - 30-gon

At a regular 30-gon the radius of the inscribed circle is 15cm. Find the "a" side size, circle radius "R", circumference, and content area. - Cuboid - ratios

The sizes of the edges of the cuboid are in the ratio 2: 3: 5. The smallest wall have area 54 cm^{2}. Calculate the surface area and volume of this cuboid. - Diagonal of the rectangle

Calculate the diagonal of the rectangle which area is 54 centimeters square and the circuit is equal to 30 cm. - Unknown number 24

f we add 20, we get 50% of its triple. What is this unknown number?

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