New math problems - page 5

  1. Pets in ZOO
    chicken_3 The zoo have run for pets. They are chickens, pigs and cow. Altogether there has 20 heads and 60 feet. How many chickens and piglets are there?
  2. Subjects
    math_series_1 Student makes a mathematical task for five minutes and the task from biology in twelve minutes. Another day he have homework in math and biology which consists of eleven tasks together. To do the job took hour and a half. How many tasks maked in each subje
  3. Evaluate expression
    mixed_fractions.JPG Evaluate expression using BODMAS rule: 1 1/4+1 1/5÷3/5-5/8
  4. Cube and sphere
    gule_1 Cube with the surface area 150 cm2 is described sphere. What is sphere surface?
  5. Ice and water
    ice_playground We want to cover rectangular rink with dimensions of 55 m and 25 m with 4cm thick layer of ice. How many liters of water we need if after freezing water increases its volume by 10%?
  6. Cuboids
    3dvectors Two separate cuboids with different orientation in space. Determine the angle between them, knowing the direction cosine matrix for each separate cuboid. u1=(0.62149553, 0.11709336, 0.77461762) u2=(0.046501848, 0.66652649, 0.74402958)
  7. Rhombus and diagonals
    kosostvorec_2 The a rhombus area is 150 cm2 and the ratio of the diagonals is 3:4. Calculate the length of its height.
  8. Points in plane
    linear_eq_1 The plane is given 12 points, 5 of which is located on a straight line. How many different lines could by draw from this points?
  9. Apples 2
    jablka_6 Dried apples contain 15% water. Fresh apples contain 80% water. How many kg of apples we need buy in order to get 3 kg of dried apples?
  10. 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?
  11. Family
    family_5 Son is 3/5 smaller than the mother. Mother is 99 cm higher than the son. How tall is the mother?
  12. Toy store
    panenka In the toy department of store was exposed 28 dolls. 19 dolls were blondes or could speak. 12 dolls were blondes, 14 could speak. How many blondes could speak in the toy department? How many blondes could not speak?
  13. Diagonal of square
    ctverec_mo_1 Calculate the side of a square when its diagonal is 10 cm.
  14. Withdrawal
    penize_13 If I withdrew 2/5 of my total savings and spent 7/10 of that amount. What fraction do I have in left in my savings?
  15. Digit sum
    numbers_41 Determine for how many integers greater than 900 and less than 1,001 has digit sum digit of the digit sum number 1.
  16. Goat, cabbage and wolf
    goat__wolf_and_cabbage A man once had to travel with a wolf, a goat and a cabbage. He had to take good care of them, since the wolf would like to taste a.piece of goat if he would get the chance, while the goat appeared to long for a tasty cabbage. After some traveling, he sudde
  17. Medians and sides
    taznice3 Triangle ABC in the plane Oxy; are the coordinates of the points: A = 2.7 B = -4.3 C-6-1 Try calculate lengths of all medians and all sides.
  18. Frameworks is bad
    space Calculate how many percent will increase the length of an HTML document, if any ASCII character unnecessarily encoded as hexadecimal HTML entity composed of six characters (ampersand, grid #, x, two hex digits and the semicolon). Ie. space as:  
  19. Isosceles - isosceles
    triangles_12 It is given a triangle ABC with sides /AB/ = 3 cm /BC/ = 10 cm, and the angle ABC = 120°. Draw all points X such that true that BCX triangle is an isosceles and triangle ABX is isosceles with the base AB.
  20. Square vs rectangle
    ctverec Square and rectangle have the same area contents. The length of the rectangle is 9 greater and width 6 less than side of the square. Calculate the side of a square.

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