Examples for 8th grade - page 15

  1. Water
    storm_1 On the lawn which has area 243 m2 rained 5 mm of water. How many liters of water rained?
  2. Jan
    Honza Jan is 13 years and Peter 21 years old. For how many years will their ages in the ratio of 7:9?
  3. Posters
    posters 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?
  4. Simple interest
    bank Peter put into bank 1028 euros deposit. After 6 years on account overall was 1242 euro. What was the interest rate if bank add simple interest?
  5. Water tank
    akvarium_1 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?
  6. Car range
    Lupo_3L_TDI.JPG Calculate the maximum range of car, if you can spend 25 euros, price of diesel is 1.55 Eur/l and car consumption is 6.4 l/100 km.
  7. Enrollment
    enrollment 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).
  8. Scale
    pool_1 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?
  9. Movement
    peleton 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.
  10. Basements
    Spider-and-Fly 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.
  11. Mushrooms
    mushrooms-01 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?
  12. Five tractors
    tractor_1 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?
  13. Isosceles trapezoid
    licho_1 Calculate the area of an isosceles trapezoid whose bases are in the ratio of 4:3; leg b = 13 cm and height = 12 cm.
  14. Distance
    origin_math Wha is the distance between the origin and the point (23; -7)?
  15. Goods
    money To the market is introducing a new product, the first week is sold at a reduced price. 5 products is sell at an entry price same as 3 products at the normal price. How much % is reduced price less than the current price for this product?
  16. Combinatorics
    fontains The city has 7 fountains. Works only 6. How many options are there that can squirt ?
  17. Similarity
    rectangles_1 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.
  18. Coffee
    coffe 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?
  19. Rectangle
    rectangle_ABCD 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 ?.
  20. Tangents
    tangents 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.

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