Examples for 8th grade - page 43
Calculate the length of the diagonal AC of the rhombus ABCD, if its perimeter is 352 dm and the other diagonal BD has length 148 dm.
Calculate how much money per year would go to the treasury of unions if 447 thousand employee join unions with an average net salary of 539 euros and if memberhip in union cost 1% of the net monthly salary.
Base of building is circle with diameter 39 m. Calculate the circumference of a circular trench witch diameter is 21 cm wider than the diameter of the base.
- Cu wire
Copper wire has a length l = 210 m and diameter d = 10 mm. Calculate the weight if density of copper is ρ = 8500 kg/m3. Result round to one decimal place.
- Square Number
If to a square of integer number add 49, we get the square of next integer number. What is the original number?
Road has climbing 1:23. How big is a angle corresponds to this climbing?
How far can you see from the ship's mast, whose peak is at 11 meters above sea level? (Earth's radius is 6370 km).
Surface of the sphere is 2260 cm2, weight is 52.2 kg. What is its density?
VAT is a tax which the state artificially betrays goods and services for final consumption. VAT in Slovakia is 20%. Calculate how much percent pay less tax residents of Switzerland, when VAT is only 8%.
- Triangle SAS
Calculate area and perimeter of the triangle, if the two sides are 19 cm and 80 cm long and angle them clamped is 90°.
The rectangular crossroads comes passenger car and an ambulance, the ambulance left. Passenger car is at 45 km/h and ambulance 58 km/h. Calculate such a relative speed of the ambulance moves to the car.
Two boys started from one place. First went north at velocity 3 m/s and the second to the east with velocity 4 m/s. How far apart they are after minute?
Gasoline is stored in a cuboid canister having dimensions 44.5 cm, 30 cm, 16 cm. What is the total weight of a full canister when one cubic meter of gasoline weighs 710 kg and the weight of empty canister is 1.5 kg?
A pit is dug in the shape of a cuboid with dimensions 10mX8mX3m. The earth taken out is spread evenly on a rectangular plot of land with dimensions 40m X 30m. What is the increase in the level of the plot ?
- Train expres
At 8.00 strarted from Bratislava to Poprad express Tatry. Cities are distant 340 kilometers. At the same time started from Poprad express Danube to Bratislava. Express Tatry's average speed is 80 km/h, Danube 90 km/h. At what distance from Poprad trains w
From the money that was in my Maria wallet she spent a fifth on the first purchase. From remain money she could buy 2 kg of strawberries. But she bought only 1.5 kg for 60 Kc. How much money was Marie originally in her wallet?
- Reduce of the volume
Calculate how many % reduce the volume of the cube is we reduced length of each edge by 10%.
Peter, Jane and Thomas have together € 550. Tomas has 20 euros more than Jane, Peter € 150 less than Thomas. Determine how much has each of them.
Calculate the percentage of waste if the cube with 52 cm long edge is lathed to cylinder with a maximum volume.
- Cube 7
Calculate the volume of a cube, whose sum of the lengths of all edges is 276 cm.