Examples for 8th grade - page 40

  1. 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
  2. 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).
  3. 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?
  4. Cylinder
    cylinder The cylinder surface is 859 dm2, its height is equal to the radius of the base. Calculate height of this cylinder.
  5. 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?
  6. 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.
  7. Comparing powers
    diagram How many times is number 56 larger than number 46?
  8. Rope
    navijak How many meters of rope 10 mm thick will fit on the bobbin diameter of 200 mm and length 350 mm (central mandrel have a diameter 50 mm)?
  9. 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.
  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. Vinegar
    vinegar_1 What percentage vinegar we get if we mix 1 if dm³ eight percent vinegar with 1.5 dm³ six percent vinegar?
  12. 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?
  13. 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?
  14. 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?
  15. Parallelogram
    rovnobeznik_1 Parallelogram has sides lengths in the ratio 3: 4 and perimeter 2.8 meters. Determine the lengths of the sides.
  16. 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?
  17. Arc
    vysek What area of a circle occupied the flowers planted in the arc of a circle with radius 4 m with central angle 45°?
  18. Round table
    obrus-kruhovy Round table with diameter d = 105 cm is coated by square tablecloth with a side length 121 cm. About how many cm is higher center of tablecloth than its cornes?
  19. 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?
  20. Square Number
    squared-number If to a square of integer number add 31, we get the square of next integer number. What is the original number?

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