Examples for 8th grade - page 16
Column with posters in the form of a cylinder is 3.3 m high and its diameter is 1.5 m. What is the content area for which it is possible to stick posters?
- Inflow - outflow
The tank will fill by inflow for 93 minutes and empties by outflow for 104 minutes. How long take to fill tank if it is also opened the inflow and outflow?
In rectangle ABCD with sides |AB|=11, |AD|=12 is from point A guided perpendicular to the diagonal BD, which intersects at point P. Determine the ratio ?.
Find all divisors of number 418. How many are them?
- Degrees to radians
Convert magnitude of the angle α = 618°40'29" to radians:
To circle with a radius of 98 dm from the point A guided two tangents. The distance of both points of contact is 155 dm. Calculate the distance from point A and circle centre.
- A family
A family of four pays for garbage collection per year 1800 Kč. How many crowns a year the waste company get from the house where lives 93 people?
On the lawn which has area 243 m2 rained 5 mm of water. How many liters of water rained?
- Water tank
Water tank shape cuboid has a width of 3.3 m and length twice larger. How high will reach water if water flow into 15 liters of water per second during 23 minutes?
The enrollment at a local college increased 3% over last year's enrollment of 7145. Find the increase in enrollment (x1) and the current enrollment (x2).
Rectangle ABCD has dimensions of 9 cm and 6 cm. Rectangle PQRS has dimensions 7 cm and 8 cm. Determine coefficient of the similarity k of the rectangles, if they aren't similar enter zero as the coefficient of similarity.
Swimming pool is long 110 m and 30 m wide. The plan of the city is shown as a rectangle with area 13200 cm2. What scale is the city plan?
In stock are three kinds of branded coffee prices: I. kind......5.3 USD/kg II. kind......11.6 USD/kg III. kind.....5.8 USD/kg Mixing these three species in the ratio 2:8:3 create a mixture. What will be the price of 800 grams of this mixture?
From the crossing of two perpendicular roads started two cyclists (each at different road). One runs at average speed 18 km/h, the second at average speed 24 km/h. Determine the distance between them after 30 minutes cycling.
In the first basement is more flies than the spiders, the second vice versa. Each basement had spiders and flies together 100 feet. Determine how many could be flies and spiders in the first and second basement. PS. We only need, when you write how many.
For five days, we have collected 410 mushrooms. Interestingly every day we have collected 10 mushrooms more than the preceding day. How many mushrooms we have collected during 4th day?
Peter chops wood. If they cut down a half hours a day he ended work in 9 days. But Peter needs to end work 3 days earlier. How many minutes a day should cut down?
- Five tractors
Five tractors plow field in 4.8 hours. How long plow this field if after 1.5 hours of work two tractors went to a different field?
- Isosceles trapezoid
Calculate the area of an isosceles trapezoid whose bases are in the ratio of 4:3; leg b = 13 cm and height = 12 cm.
- The camp
At the end of the camp a 9 friends exchanged addresses. Any friend gave remaining 8 friends his card. How many addresses they exchanged?