Examples for 9th grade - page 72

  1. Divisible by 5
    175px-5th_MarDiv How many three-digit odd numbers divisible by 5, which are in place ten's number 3?
  2. Brick wall
    plot_zed Garden 70 m long and 48 m wide should surround with wall 2.1 meters high and 30 cm thick. How many we will need bricks if to 1 m³ is needed approximately 300 bricks?
  3. Three-digit
    seven How many three-digit natural numbers do not have the number 7?
  4. Bags
    kufor The first bag has a weight of 18 kg, the second bag is a one-third lighter than the first and the third bag has three times less the weight of all three bags together. Determine their weights.
  5. Angles in ratio
    angles_1 The size of the angles of the triangle are in ratio x: y = 7: 5 and the angle z is 42° lower than the angle y. Find size of the angles x, y, z.
  6. Cuboid enlargement
    cubes_12 By how many percent increases the volume of cuboid if its every dimension increases by 30%?
  7. Water reservoir
    vodojem The reservoir shape of a cylinder having a diameter 8 m and a height 2.8 m. The device indicates that the reservoir contains 800 hectoliters of water. Calculate how much % of volume is used.
  8. AP 6
    progression_ao Calculate the first five items of an arithmetic sequence if it is given: a2 – a3 + a5 = 20 a1 + a6 = 38
  9. Body diagonal
    cubes3_1 Find the cube surface if its body diagonal has a size of 6 cm.
  10. Four friends
    money_10 Four friends shared the money. Vasek got 1/4 of the total amount. Tonda received 1/3 of the rest of the money, Joe got a half from the second residue and Jirka left 80. How much money get together?
  11. Axial cut
    Kuzel The cone surface is 388.84 cm2, the axial cut is an equilateral triangle. Find the cone volume.
  12. Balls
    spheres_1 The urn is 8 white and 6 black balls. We pull 4 randomly balls. What is the probability that among them will be two white?
  13. Remuneration
    cnb Total remuneration for workers is 47 000 CZK. The second worker received 20% more than the first and third 4000 CZK less than a second employee. How many CZK each received?
  14. Garden
    garden_7 The garden has a rectangular shape with lengths of 25 and 40 meters. It has been expanded so that each of its size increased by one fifth. How many square meters increased its acreage?
  15. Krkonose CZ
    krkonose Tourist's rod on the tourist route in the Krkonose was 1/5 of its length into the ground. Snow fell in winter and 1/3 of the length of the rod remained above the snow. Find the height of the snow if the length of the part above the snow is 32 cm greater t
  16. Failure
    car_12 Drivers of passenger cars have calculated that at a speed of 60 km/h arrives at destination within 40 minutes. After 20 km refrain five minutes due a technical failure. How fast must go the rest of the way to the finish came at the scheduled time?
  17. Sum of three numbers
    bulb2_4 The sum of three numbers from which second number is 20% smaller than the first number and the third number is 25% smaller than the second number is 96. Determine this numbers.
  18. Tree shadow 3
    tree3_1 A 2-meter rod casts a shadow 3.2 m long. How high is a tree with a shadow of 14.4 m ?
  19. The ladder
    rebrik33_1 The ladder is 10 m long The ladder is 8 m high How many meters is the distant heel from the wall?
  20. Linear function
    intersection_fn_1 What is the equation of linear function passing through points: a) A (0,3), B (3,0) b) A (-2,-6), B (3,4)

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