Examples for 8th grade - page 40

  1. Pool 2
    bazen_pritok The first supply by the pool fill for five hours and the second fill for six hours, drain should be drained for 15 hours. For how many hours the pool is full, when we open both inlet now and outlet open two hours later?
  2. Word problem
    hungary-flag 395 students were on holiday in Hungary. 110 bought pizza, chips 21 pupils, 26 pupils bought soda, butter 18 pupils, 12 pupils fruits, vegetables 29 students. How much pay for all the food, if every meal cost 5.5 euros?
  3. Digits A, B, C
    numbers_8 For the various digits A, B, C is true: the square root of the BC is equal to the A and sum B+C is equal to A. Calculate A + 2B + 3C. (BC is a two-digit number, not a product).
  4. Three numbers
    fun3_8 The sum of the three numbers is 287. These numbers are in a ratio of 3: 7: 1/4 Define these numbers
  5. Cylinder
    cylinder The cylinder surface is 859 dm2, its height is equal to the radius of the base. Calculate height of this cylinder.
  6. Vinegar
    vinegar_1 What percentage vinegar we get if we mix 1 if dm³ eight percent vinegar with 1.5 dm³ six percent vinegar?
  7. Equator
    around_globe Suppose that tourist went on foot over the Globe equator. How many meters more track made ​​his hat on his head as the shoes on your feet? The radius of the earth is 6378 km and height of the tourist is 1.7 m.
  8. Medal
    gold_medail Calculate the approximate weight of the gold Olympics medal, if its diameter is 8 cm and a thickness 6 mm. The density of gold find out in the tables or on the Internet.
  9. Sheep
    ships Shepherd tending the sheep. Tourists asked him how much they have. The shepherd said, "there are fewer than 500. If I them lined up in 4-row 3 remain. If in 5-row 4 remain. If in 6-row 5 remain. But I can form 7-row." How many sheep have herdsman?
  10. Nuts, girl and boys
    orechy_nuts Milena collected fallen nuts and called a bunch of boys let them share. She took a condition: the first boy takes one nut and tenth of the rest, the second takes 2 nuts and tenth new rest, the third takes 3 nuts and tenth new rest and so on. Thus managed.
  11. Comparing powers
    diagram How many times is number 56 larger than number 46?
  12. Aquarium 6
    water_aquarium How high is the water level in the aquarium with a rectangular base 40cm and 50cm if it is filled 0,65hl of water?
  13. Acute angles
    angles_meter Sizes of acute angles in the right-angled triangle are in the ratio 1: 3. What is size of the larger of them?
  14. Two boxes-cubes
    3-kostky Two boxes cube with edges a=38 cm and b = 81 cm is to be replaced by one cube-shaped box (same overall volume). How long will be its edge?
  15. Bouquet
    flowers_1 Gardener tying bouquet of flowers for 8 and none was left. Then he found that he could tying bouquet of 6 flowers and also none was left. How many have gardener flowers (minimum and maximum) if they had between 50 and 100 flowers?
  16. Parallelogram
    rovnobeznik_1 Parallelogram has sides lengths in the ratio 3: 4 and perimeter 2.8 meters. Determine the lengths of the sides.
  17. Cars
    car_red Cars started at 7:00 AM. From point A car run at 40 km per hour, from B car run 70 km per hour. Between A and B is 250 km long road. When and where will meet (measured from point A)?
  18. Parallelogram +ľ
    rovnobeznik_2.JPG | AB | = 76cm, | BC | = 44cm, angle BAD = 30 °. Find the area of the parallelogram.
  19. Motion 2
    motion2 At 10 o'clock started from place A car speed at 90 km/h. 20 minutes after started from the place B at speed 60 km/h another car. Distance places A and B is 120 kilometers. What time and where they meet?
  20. Tetrahedral pyramid
    jehlan_3 It is given a regular tetrahedral pyramid with base edge 6 cm and the height of the pyramid 10 cm. Calculate the length of its side edges.

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