Examples for 9th grade - page 53

  1. Addends
    two Number 118 divide into two addends, so first addend is 69 greater than 75% of the second addend.
  2. Forces
    resultant_force Determine the resultant of two perpendicular forces F1 = 560 N and second force of 25% smaller.
  3. Sweets
    sladkosti 3 chocolate and 7 cakes cost 85, - CZK. 2 chocolates and 6 cakes cost 86, - CZK. How much is 5 chocolates and 9 cakes? I wonder how to get the result, but only by logic without the use of a system of equations
  4. Friends
    friends2 Some friends had to collect the sum 72 EUR equally. If the three refused their part, others would have to give each 4 euros more. How many are friends?
  5. 4side pyramid
    ihlany Calculate the volume and surface of 4 side regular pyramid whose base edge is 4 cm long. The angle from the plane of the side wall and base plane is 60 degrees.
  6. Chimney
    komin_melnik Lower circumference of of the chimney is 12.57 m, top circumference is 5.655 m. The slope of the walls is 87°. Determine the height of the chimney.
  7. Cube from sphere
    sphere_cube What largest surface area (in cm2) can have a cube that was cut out of a sphere with radius 3 cm?
  8. Clock
    timer What distance will pass end of 8 cm long hour hand for 15 minutes?
  9. Dollars
    children Mama split 760 dollars Jane, Dane and Eva as follows: Jane got three times more than Dane and Dane and got 40 more than Eva. How much does get each of them?
  10. Two boxes-cubes
    3-kostky Two boxes cube with edges a=74 cm and b = 91 cm is to be replaced by one cube-shaped box (same overall volume). How long will be its edge?
  11. Sphere area
    sphere A cube with edge 1 m long is circumscribed sphere (vertices of the cube lies on the surface of a sphere). Determine the surface area of the sphere.
  12. 3 years
    ekonomicky-rast The company has increased the number of employees. In year 1997 compared to 1996 17% more, in 1998 12% more against the previous year, in year 1999 20% more compared to 1998. How many % increase in the number of employees in 3 years?
  13. Paper box
    cuboid_5 Calculate the consumption of paper on the box-shaped quadrangular prism with rhombic footstall, base edge a=6 cm and the adjacent base edges forms an angle alpha = 60 °. Box height is 10 cm. How many m2 of the paper consumed 100 such boxes?
  14. Surface area
    cone_slice The volume of a cone is 1000 cm3 and the content area of the axis cut is 100 cm2. Calculate the surface area of the cone.
  15. 3 days
    kontrolor Worker checked 2,950 products in 3 days. Second day checked 25% more than the first day. The third day 15% more products than the second day. How many products he checked in each day.
  16. Chord 3
    chords What is the radius of the circle where the chord is 2/3 of the radius from the center and has a length of 10 cm?
  17. The hall
    lucerna The hall had a rectangular ground plan one dimension 20 m longer than the other. After rebuilding the length of the hall declined by 5 m and the width has increased by 10 m. Floor area increased by 300 m2. What were the original dimensions of the hall?
  18. Orchard
    lichobeznik_1 Route passes trapezoidal orchard perpendicular to the parallel sides. It is 80 cm wide. The lengths of the bases are in the ratio 5:3 and the length of the longer base to the length of the path is in the ratio 5:6. How many square meters occupies the rou
  19. Antennas
    antenas If you give me two antennas will be same. If you give me again your two antenna I have a 5× so many than you. How many antennas have both mans?
  20. Profits
    podnikavec Two members will make profit 52 000, - EUR. The forst earned 8% more and the second 10% more and thus earned together 56 700, - EUR. How many will initially each earn?

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