Grade - examples - page 133

  1. 30-gon
    30gon At a regular 30-gon the radius of the inscribed circle is 15cm. Find the "a" side size, circle radius "R", circumference, and content area.
  2. Circle from string
    motuz Martin has a long 628 mm string . He makes circle from it. Calculate the radius of the circle.
  3. Disc
    vysek.JPG Circumference of the disk is 78.5 cm. What is the circumference of the circular arc of 32° on the disc?
  4. Coins
    coins Denis and Zdeno together have 97 coins. If Denis had 4 coins less than he has now, the number of the coins would be in the ratio 14: 17. Determine the number of coins owned by Denis and Zdeno.
  5. Fuel economy
    car1_4 How many kilometers is sufficient petrol in the cylinder fuel tank with a diameter 40 cm and the base of tank length 1 m, when it is filled to 60% and if the car consume 15 liters per 100 km?
  6. Charles Bridge
    k_most Charles Bridge was 15 times older than Frantův bridge from 1900 in 1931. How old is the Charles Bridge?
  7. Perpetrator
    snehulaci The perpetrator is a number that is smaller than the number 80. It is a multiple of five and it is odd. If we added up the tens and ones of this number we get number 8.
  8. Decide
    mo_1 The rectangle is divided into seven fields. On each box is to write just one of the numbers 1, 2 and 3. Mirek argue that it can be done so that the sum of the two numbers written next to each other was always different. Zuzana (Susan) instead argue that.
  9. Percent
    percentage_2 Calculate how many % is the number 26.25 less than the number 105.
  10. Roses and tulips
    flowers_3 At the florist are 50 tulips and 5 times less roses. How many flowers are in flower shop?
  11. Cube surface area
    cubes2_2 The surface of the cube was originally 216 centimeters square. The surface of the cube has shrunk from 216 to 54 centimeters sq. Calculate how much percent the edge of the cube has decreased.
  12. Percentage - fractions
    rubik About what percentage we must increase number 1/6 to get number 1/3?
  13. Pharmacy
    roztoky_3 The pharmacy add to 3 liters of 95-percent alcohol 5 liters of 38.04 percent alcohol. How many percent pharmacy got?
  14. Tank
    nadrz_5 To cuboid tank whose bottom has dimensions of 9 m and 15 m were flow 1080 hectoliters of water. This was filled 40% of the tank volume. Calculate the depth of the tank.
  15. Unknown number 7
    graph-parabola Calculate unknown number whose 12th power when divided by the 9th power get a number 27 times greater than the unknown number. Determine the unknown number.
  16. Circle - simple
    colorful-circle Calculate the area of a circle in dm2, if its circumference is 31.4 cm.
  17. Infinite decimal
    series Imagine the infinite decimal number 0.99999999 .. ... ... ... That is a decimal and her endless serie of nines. Determine how much this number is less than the number 1. Thank you in advance.
  18. Unknown number
    nums Identify unknown number which 1/5 is 40 greater than one tenth of that number.
  19. Cylinder surface area
    cylinder_2 Volume of a cylinder whose height is equal to the radius of the base is 678.5 dm3. Calculate its surface area.
  20. Common cylinder
    valec_2 I've quite common example of a rotary cylinder. Known: S1 = 1 m2, r = 0.1 m Calculate : v =? V =? You can verify the results?

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