Examples for 8th grade - page 54

  1. Stamps and albums
    stamp Michail has in three albums stored 170 stamps. In the first album, there are 14 more than in the second and in the second is by 1/5 less than in the third. How many stamps are in the first album?
  2. Number
    percent What number is 24 % smaller than the number 51?
  3. Cuboid walls
    cuboid_9 Calculate the volume of the cuboid if its different walls have area of 195cm², 135cm² and 117cm².
  4. Double-track
    vlak_1 On double-track express met with a freight train. Express travel at speed 72 km/h, a freight train at speed 36 km/h. After what time period will be from 9 km apart?
  5. President
    bush_president The country has 5.9 million citizens which 2.24 million are voters. Turnout was 39.9%. President R. F. was elected from 19 candidates for president and won with 28% of votes. Calculate what percentage of the country's citizens voted R.F. as president of
  6. Football season
    futball Throughout the football season gave Adam the 23 goals more than Brano and 16 goals less than Karol. Edo gave the 6 goals more Dušan. Karol gave 5 more than Edo. Brano and Edo gave together 17 goals. How many goals gave each boy and how many goals gave the.
  7. Fraction
    polynomial For what x expression ? equals zero?
  8. High wall
    mur I have a wall 2m high. I need a 15 degree angle (upward) to second wall 4 meters away. How high must the second wall?
  9. Prism
    prism Base of perpendicular triangular prism is a right triangle with cathetuses 4.5 cm and 6 cm. What is the surface of the prism, if its volume of 54 cubic centimeters.
  10. Bob and Bobek
    bob_a_bobek At 10h 20min runs Bobek from hat at average speed 12 km/h. At what time must run out Bob at speed 18 km/h to catch him 9 kilometers from the hat?
  11. Painting
    basen_7 To paint the pool with dimensions: 2 meters depth, 3m x 4m we bought paint to 50 meters square. How many "paint" will be a waste?
  12. Cleaners
    clean Milan would clean up the room for 2.5 hours, Eric would take 10 hours. How long they swept the room together?
  13. Reduce of the volume
    cubes Calculate how many % reduce the volume of the cube is we reduced length of each edge by 10%.
  14. Boots
    vysoke-cizmy Master shoemaker has three apprentices. First do one pair of boots for two days, second for 1 day, third on 1.5 day. If they worked together, for how long it would take made a couple of boots?
  15. Concrete box
    truhlik The concrete box with walls thick 7 cm has the following external dimensions: length 1.7 m, width 31 cm and height 45 cm. How many liters of soil can fit if I fill it to the brim?
  16. V - slope
    verticals The slope of the line whose equation is 8x +8 = 0 is
  17. Powers
    1power Express the expression ? as the n-th power of the base 7.
  18. Tiles
    dlazba How much you will pay CZK for laying tiles in a square room with a diagonal of 8 m if 1 m2 cost CZK 420?
  19. Waiting room
    fly In the waiting room are people and flies. Together they have 15 heads and 50 legs (fly has 6 legs). How many people and flies are in the waiting room?
  20. Box of chocolates
    zele-bonbony In a box of chocolates was 16 candies. Christopher and Luke they were distributed: a) Christopher had about 4 candies over Luke, b) Christopher had about 6 candies less than Luke, c) Christopher had 3 times more sweet than Luke. How many had each boy can

Do you have interesting mathematical example that you can't solve it? Enter it and we can try to solve it.

To this e-mail address we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.