Examples for 8th grade - page 53

  1. MATES
    sazka In MATES (Small Television tipping) from 35 randomly numbers drawn 5 winning numbers. How many possible combinations there is?
  2. Percent
    skiing From 99 children who participated in the ski course were 23 excellent skiers, 13 good and 20 average and the rest were beginners. Calculate this data in percentages.
  3. Fifth of the number
    numbs_5 The fifth of the number is by 24 less than that number. What is the number?
  4. Ratio of two unknown numbers
    numbers2_23 Two numbers are given. Their sum is 30. We calculate one-sixth of a larger number and add to both numbers. So we get new numbers whose ratio is 5:7. Which two numbers were given?
  5. Fewer than 500 sheep,
    sheep-500 There are fewer than 500 sheep, but if they stand in a double, triple, quadruple, five and sixth order, one sheep will remain. But they can stand in the seventh order. How many are sheep?
  6. Interest p.a.
    2dane-peniaze Calculate the value of interest in period of 1 year from the deposit 62000 CZK at 8 percent interest rate, after deducting 15 percent tax.
  7. Travel by bus
    cats_1 Five girls traveling by bus. Each holds in each hand two baskets. Each basket contains 5 cats. Each cat has 5 kittens. 3 girls getting off the bus and another girl without baskets go on board. The bus control driver. How many legs are in the bus?
  8. Arc-sector
    vzorec arc length = 17 cm area of sector = 55 cm2 arc angle = ? the radius of the sector = ?
  9. Rectangular field
    field One dimension of the rectangular field is 56 m greater than second dimension. If each side of the rectangle increases by 10 m, increases the surface field is 1480 m2 . Determine dimencions of the field.
  10. Extreme temperatures
    heat_weather USA hit extreme heat wave. Calculate percentage of the air temperature change from normal summer temperature 23 °C to 40 °C.
  11. Segment in a triangle
    priecka In a triangle ABC with the side/AB/ = 24 cm is constructed middle segment/DE/ = 18 cm parallel to the side AB at a distance 1 cm from AB. Calculate the height of the triangle ABC to side AB.
  12. Obtuse angle
    10979326_654459541349455_1236723697_n The line OH is the height of the triangle DOM, line MN is the bisector of angle DMO. obtuse angle between the lines MN and OH is four times larger than the angle DMN. What size is the angle DMO? (see attached image)
  13. Three men
    GUYS Alex is half younger than Jan, which is one-third younger than George. The sum of their ages is 48. How are these three men old?
  14. The field
    plavec_1 The player crossed the field diagonally and walked the length of 250 m. Calculate the length of the field, circumference if one side of field 25 meters.
  15. Tray
    vanicka Wjat height reach water level in the tray shaped a cuboid, if it is 420 liters of water and bottom dimensions are 120 cm and 70 cm.
  16. Arithmetic average
    ap The arithmetic mean of the five numbers is exactly 8. The sum of these four numbers is 30. What is the fifth number?
  17. Square circles
    stvorec_kruh Calculate the length of the described and inscribed circle to the square ABCD with a side of 5cm.
  18. Sputnik
    sputnik The first Earth satellite was flying at speed 8000 m/s. At that rate he circled the earth in 82 minutes. Jet flies at an average speed 800 km/h. How long would it take circle the earth round?
  19. The city
    m_f In the city is 2/4 of women married to 3/4 men. What percentage of townspeople is single (not married)?
  20. Mr. John
    jabka Mr. John wants to buy winter apples Spartan. There are two ways to buy: 1) buy apples at the marketplace, where 1 kg costs 15 CZK. 2) Bring the car to the agricultural farm, where the apples are sold after 9 CZK per kilogram. However, he must pay CZK 150.

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