Grade - examples - page 92

  1. Triangle
    triangle_inequality Determine if it is possible to construct a triangle with sides 28 31 34 by calculation.
  2. Unknown number
    unknown Unknown number is divisible by exactly three different primes. When we compare these primes in ascending order, the following applies: • Difference first and second prime number is half the difference between the third and second prime numbers. • The produ
  3. 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?
  4. Rhombus
    rhombus-diagonals_3 One angle of a rhombus is 136° and the shorter diagonal is 8 cm long. Find the length of the longer diagonal and the side of the rhombus.
  5. Rope
    lano Peter has a long rope 2 4/5 meter. Martin has a rope 20 cm longer. What distance ropes achieved if the boys link ropes?
  6. Pipe
    trubka_ocel Steel pipe has a length 2.5 meters. About how many decimetres is 1/3 less than 4/8 of this steel pipe?
  7. Square circles
    stvorec_kruh Calculate the length of the described and inscribed circle to the square ABCD with a side of 5cm.
  8. Velocipede
    velociped The front wheel of velocipede from year 1880 had a diameter 1.8 m. If the front wheel turned again one then rear wheel 6 times. What was the diameter of the rear wheel?
  9. Rectangle pool
    basen_5 Determine dimensions of open pool with a square bottom with a capacity 32 m3 to have painted/bricked walls with least amount of material.
  10. 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?
  11. 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.
  12. Laths
    garaz There are two laths in the garage opposite one another: one 2 meters long and the other 3 meters long. They fall against each other and lean against the opposite walls of the garage both laths and touch at a height of 70 cm above the garage floor. How wide
  13. Concrete tank
    beton How many m3 of concrete is in the tank shape of a cuboid with dimensions of 2000 cm and 5.6 meters and 70 dm, if the concrete takes up 3/7 of the tank?
  14. Chestnuts
    gastany_1 Mary harvested 45 chestnuts. Christian harvested 56 chestnuts more. How many chestnuts gathered together?
  15. 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)?
  16. 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.
  17. 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?
  18. Right triangle
    right_triangle Right triangle legs has lengths 630 mm and 411 dm. Calculate the area of this triangle.
  19. Tubes
    pipes_1 Iron tubes in the warehouse are stored in layers so that each tube top layer fit into the gaps of the lower layer. How many layers are needed to deposit 100 tubes if top layer has 9 tubes? How many tubes are in bottom layer of tubes?
  20. The creek
    potok Workers cleaned the creek within 3 days. The first day cleanse one-fifth the length of the creek, the next day 40% of the length of the stream and the third day 8 km length of the creek. How long is a creek?

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