# Volume - 8th grade (13y) - examples - page 12

1. Pharmacy
The pharmacy add to 3 liters of 95-percent alcohol 5 liters of 38.04 percent alcohol. How many percent pharmacy got?
2. Cylinder surface area
Volume of a cylinder whose height is equal to the radius of the base is 678.5 dm3. Calculate its surface area.
3. Common cylinder
I've quite common example of a rotary cylinder. Known: S1 = 1 m2, r = 0.1 m Calculate : v =? V =? You can verify the results?
4. Pool
The pool has the shape of a cylinder with a diameter 4.6m, the presumed height is 130cm. The bucket fits 12l of water. How many buckets do you have to bring to fill this pool?
5. Fuel mileage
You have 3/8 tank of fuel. Estimate fuel consumption @ 6mpg. Estimate speed @ 50mph. Your fuel tank holds 200 gals. Figure out fuel mileage.
6. Percentages
Calculate the percentages to two decimal places: a / 15 min in 4 hours B / 35 cm2 of 12.5 dm2 c / 2dm2 of 400 cm2 D / 0.2 liters from 2.2 liters
7. Brick wall
Garden 70 m long and 48 m wide should surround with wall 2.1 meters high and 30 cm thick. Wall will be built on the garden ground. How many will we need bricks if to 1 m³ is required approximately 300 bricks?
8. Roof 8
How many liters of air are under the roof of tower which has the shape of a regular six-sided pyramid with a 3,6-meter-long bottom edge and a 2,5-meter height? Calculate the supporting columns occupy about 7% of the volume under the roof.
9. Cuboid enlargement
By how many percent increases the volume of cuboid if its every dimension increases by 30%?
10. Water reservoir
The reservoir shape of a cylinder having a diameter 8 m and a height 2.8 m. The device indicates that the reservoir contains 800 hectoliters of water. Calculate how much % of volume is used.
11. Conva
How many liters of water fit into the shape of a cylinder with a bottom diameter 20 cm and a height 45 cm?
Find the volume and surface of a regular quadrilateral pyramid if the bottom edge is 45 cm long and the pyramid height is 7 cm.
13. Cooling liquid
Cooling liquid is diluted with water in a ratio of 3:2 (3 parts by volume of coolant with 2 volumes of water). How many volumes of coolant must be prepared for a total 0.7 dm3 (liters) of the mixture?
14. Iron cast
What is the weight of cast iron with volume 3575 cubic centimeters. The density of the cast iron is 7600 kg/m3
15. Metal pyramid
Find the weight of a regular quadrilateral pyramid with a 5 cm length and 6,5 cm body height is made from material with density g/cm3.
16. Cylinder
In a 1-meter diameter cylinder is 1413 liters of water, which is 60% of the cylinder. Calculate the cylinder height in meters, do not write the units. The resulting value round and write as an integer.
17. Trench
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.
18. 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.
19. Alcohol mixture
Three liters of 96 percent alcohol we set up a certain amount of distilled water to form a 54-percent alcohol. How many liters of distilled water were used?