Examples for 9th grade - page 25

  1. Pizza
    pizza_2 Pizza with a diameter 41 cm have weight 531 g. What diameter will have a pizza weighing 749 g if it is make from the same cloth (same thickness....) and same decorated?
  2. The professor's birthday
    prof_einstein Professor of mathematics had 36 birthdays. The director congratulated him. The professor asked the director: "And how old are you?" The director replied: "I'm exactly twice as many years than you were when I was old as to you today." How old is the direc
  3. Flowerbed
    flowers On the flowerbed was planted 310 flowers - pansies and crayons. During the first week wilts quarter of pansies and an eighth crayons, which is 20% of all flowers. How many pansies were planted on the flowerbed?
  4. Scale
    valec_vykres Cylinder was drawn in scale 7:1. How many times is the volume of the cylinder smaller in reality?
  5. Equilateral triangle
    3angle_in_circle How long should be the minimum radius of the circular plate to be cut equilateral triangle with side 7 mm from it?
  6. Triangle TBC
    isosceles_triangle TBC is isosceles triangle with base TB with base angle 52° and legs length |TC| = |BC| = 30. How long is the base TB?
  7. Chord
    chord In a circle with radius r=11 cm is chord 4× longer than its distance from the center. What is the length of the chord?
  8. Four swords
    fight Obelix has three helmets, four swords and five shields. How many swords must make at the blacksmith forge Metallurgix to be able to walk another 90 days in unique armor?
  9. Pears
    hrusky Andrew, Lenka and Rasto have together 232 pears. Lenka has 28 more than Rasto and Rasto pears have 96 more than Andrew. Determine how much each of them has pears.
  10. Hydrochloric acid
    hcl Determine the concentration of which must have a solution of hydrochloric acid that mixing 10 l of the solution with 8 liters of 26% solution to get the solution with a concentration of 50%?
  11. Solution
    chemia What amount of 80% solution and what amount of water is needed to mix in order to obtain two liters of 60% solution of this mixture?
  12. Age ratios
    age_1 The ratio of the age of the mother and daughter is 5:2 and after seven years the ratio will be 2:1.Before how many years was born the daughter?
  13. Liquid soap
    mydlo Liquid soap lasted two weeks to one member of the family. How many days will last, if it use: a) two members b) 4 members c) seven members?
  14. Bathroom
    koupelna How many CZK we pay for lining the perimeter walls of the bathroom with rectangular shape with dimensions 3.5 m and 4 m, high 1.5 m if 1 square m tile cost 300 CZK?
  15. Three siblings
    brothers Three siblings have birthday in one day-today. Together they have 35 years today. The youngest is three years younger than middle and the oldest is 5 years older than middle. How old is each?
  16. 12 Moons
    12_mesicku Good Marry came to ask twelve moons for help with collecting strawberries. All twelve moons 1200 strawberries picked in 20 minutes. But lazy months July and August cease tear after 5 minutes. How many minutes in total will take collect strawberries?
  17. PIN - codes
    pin How many five-digit PIN - code can we create using the even numbers?
  18. Pot
    valec_hrnec Calculate the height of 3 liter pot with shape cylinder with a diameter of 10 cm.
  19. Liters od milk
    milk_cylinder The cylinder-shaped container contains 80 liters of milk. Milk level is 45 cm. How much milk will in the container, if level raise to height 72 cm?
  20. Numbers
    primes Write smallest three-digit number, which in division 5 and 7 gives the rest 2.

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