Expression of a variable from formula - examples - page 15
The length of the rectangle is 12 cm greater than 3 times its width. What dimensions and area this rectangle has if ts circumference is 104 cm.
- Body diagonal
The cuboid has a volume of 32 cm3. Its side surface area is double as one of the square bases. What is the length of the body diagonal?
- VAT on books
The cost of a book in the store is 12.5 euros. How much euros is the VAT of this book? VAT is 10%.
The trench is a four-sided prism. The cross section has a trapezoidal shape with basements of 4m and 6m, the length of the trench is 30m. What is the depth of the trench if we dig 60,000 l of soil.
- Variance and average
Of the 40 values were calculated average mx = 7.5 and variance sx = 2.25. After the control was found to lack the two items of the values of x41 = 3.8 and x42=7. Correct the above characteristics (mx and sx).
9 workers dig a canal 120 meters long for eight hours. For how long would be dig five workers canal 200 meters long?
- Chocolate roll
The cube of 5 cm chocolate roll weighs 30 g. How many calories will contain the same chocolate roller of a prism shape with a length of 0.5 m whose cross section is an isosceles trapezoid with bases 25 and 13 cm and legs 10 cm. You know that 100 g of this.
8 employees complete the contract for 65 hours. After 17 hours, 3 employees had to leave for another job. How many more hours will the job on contract be fulfilled?
- Price saleoff
Shoes standing y euros. At first they were discounted by 12% and then 50% of the new amount. After this double cheapening the cost was exactly 22 euros. Determine the original price of shoes.
- Unknown number
Determine the unknown number, which double of its fourth square is equal the fifth its square.
Tomas spent 60% of his savings for his weekly vacation. He was 32 € left. How many euros did he have before vacation?
- Wall diagonal
Calculate the length of wall diagonal of the cube whose surface is 384 cm square.
- Quadrangular pyramid
Calculate the surface area and volume of a regular quadrangular pyramid: sides of bases (bottom, top): a1 = 18 cm, a2 = 6cm angle α = 60 ° (Angle α is the angle between the side wall and the plane of the base.) S =? , V =?
- Square s3
Calculate the diagonal of the square, where its area is 0.49 cm square. And also calculate its circumference.
- The cylinder base
The cylinder with a base of 8 dm2 has a volume of 120 liters. From a cylinder fully filled with water, 40 liters of water was removed. At what height from the bottom /with precision to dm/ is the water level?
Agricultural cooperative has increased the number of housed cows by 14% to 285 units. By how many cows increased agricultural cooperative the number of cows?
- Cube walls
Find the volume and surface area of the cube if the area of one wall is 40cm2.
A bottle of wine costs 21 euros; and wine is 20 times more expensive than a bottle. How much a bottle cost?
Three lorries droved bricks. One drove n bricks at once, second m less bricks than the first and third 300 bricks more the first lorry. The first lorry went 4 times a day the largest went 3 times a day and the smallest 5 times a day. How many bricks br
- Tank diameter
A cylindrical tank has a volume of 60 hectoliters and is 2.5 meters deep. Calculate the tank diameter.