# Expression of a variable from the formula - math problems

#### Number of problems found: 1120

• The base 2
The base diameter of a right cone is 16cm and it's slant height is 12cm. A. ) Find the perpendicular height of the cone to 1 decimal place. B. ) Find the volume of the cone, convert to 3 significant figure. Take pie =3.14
• The notebook
After rising by 40%, the notebook cost 10.50 euros. How much did this notebook cost if it increased in price by only 20% instead of 40%?
• Annual growth
The population has grown from 25,000 to 33,600 in 10 years. Calculate what was the average annual population growth in%?
• The ABCD
The ABCD trapezoid has a base length of a = 120mm, c = 86mm and an area of S = 2575 mm2. Calculate the height of the trapezoid.
• Calculate
Calculate the height of an isosceles triangle with base 37.8 mm long and an arm 23.1 mm long.
• Harmonic mean
If x, y, z form a harmonic progression, then y is the harmonic mean of x and z. Find the harmonic mean of the numbers 6 and 5.
• The land
The land, which has dimensions of 220 m and 308 m, the owner wants to divide into equally large square plots with the largest possible area. How long will one side of the plot be?
• HP - harmonic progression 2
Compute the 16th term of the HP if the 6th and 11th term of the harmonic progression are 10 and 18 respectively.
• Cube containers
Replace the two cube-shaped containers with 0.8 dm and 0.6 dm edges with a single cube-shaped one so that it has the same volume as the two original ones together. What is the length of the edge of this cube?
• Cuboid edges
The lengths of the cuboid edges are in the ratio 2: 3: 4. Find their length if you know that the surface of the cuboid is 468 m2.
• The pool
The cube-shaped pool has 140 cubic meters of water. Determine the dimensions of the bottom if the depth of the water is 200 cm and one dimension of the bottom is 3 m greater than the other. What are the dimensions of the pool bottom?
• The cube
The cube has a surface of 600 cm2. What is its volume?
• Three groups
In the company, employees are divided into three groups. In the first group, which includes 12% of the company's total number of employees, the average salary is CZK 40,000, in the second group CZK 35,000, in the third group CZK 25,000. The average salary
• Volume per time
How long does fill take for a pump with a volume flow of 200 l per minute fill a cube-shaped tank up to 75% of its height if the length of the cube edge is 4 m?
• Trapezoid 25
Trapezoid PART with AR||PT has (angle P=x) and (angle A=2x) . In addition, PA = AR = RT = s. Find the length of the median of Trapezoid PART in terms of s.
• Up and down motion
We throw the body from a height h = 5 m above the Earth vertically upwards v0 = 10 m/s. How long before we have to let the second body fall freely from the same height to hit the Earth at the same time?
• Gardens
The area of the square garden is 3/4 of the area of the triangular garden with sides of 80 m, 50 m, 50 m. How many meters of the fence do we need to fence a square garden?
• What is 10
What is the 5th term, if the 8th term is 80 and common ratio r =1/2?
• Find the 19
Find the 1st term of the GP ___, -6, 18, -54.
• If the 3
If the 6th term of a GP is 4 and the 10th is 4/81, find common ratio r.

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