Examples for 8th grade - page 19

  1. Three-digit numbers
    poker_hand_ranking How many three-digit numbers are from the numbers 0 2 4 6 8 (with/without repetition)?
  2. Distance
    origin_math Wha is the distance between the origin and the point (23; -7)?
  3. Water tank
    akvarium_1 Water tank shape cuboid has a width of 3.3 m and length twice larger. How high will reach water if water flow into 15 liters of water per second during 23 minutes?
  4. Scale
    pool_1 Swimming pool is long 110 m and 30 m wide. The plan of the city is shown as a rectangle with area 13200 cm2. What scale is the city plan?
  5. Shots
    broky 2000 lead shots with diameter 2 mm is decanted into a ball. What is it diameter?
  6. Pumps
    pumps Five pumps pumped 1,800 hl of water for 3 hours. How many hectoliters of water pump same two powerful pumps for six hours?
  7. 9.A
    exam 9.A to attend more than 20 students but fewer than 40 students. A third of the pupils wrote a math test to mark 1, the sixth to mark 2, the ninth to mark 3. No one gets mark 4. How many students of class 9.A wrote a test to mark 5?
  8. Influenza
    flu For the first week of February by influenza 5% of children in kindergarten. The second week ill 9 next children, bringing the number of patients increased to 20%. How many children went to the kindergarten?
  9. Segments
    segments Line segments 52 cm and 7.6 dm long we divide into equal parts which lengths in centimeters is expressed integer. How many ways can we divide?
  10. Goods
    money To the market is introducing a new product, the first week is sold at a reduced price. 5 products is sell at an entry price same as 3 products at the normal price. How much % is reduced price less than the current price for this product?
  11. Hexagon A
    hexagon Calculate area of regular hexagon inscribed in circle with radius r=7 m.
  12. Perpendicular
    perpendicular Determine the slope of the line perpendicular to the line p: y = 9x +7.
  13. Powers
    1power Express the expression ? as the n-th power of the base 7.
  14. Tmp workers
    profesiadays Three temporary workers cleaned 60 m of walkway in 5 hours. How many meters of the walkway cleared seven volunteers for eight hours?
  15. Construct 1
    thales_right Construct a triangle ABC, a = 7 cm, b = 9 cm with right angle at C, construct the axis of all three sides. Measure the length of side c (and write).
  16. Perimeter and legs
    RT_triangle Determine the perimeter of a right triangle if the length of one leg is 75% length of the second leg and its content area is 24 cm2.
  17. Cross-country competition
    spartakiada Cross-country competition was attended by 76% of pupils of class 9.B. Class consis of 16 boys, two of whom did not run and 4 girls did not run. How many girls go to class 9.B?
  18. Radians compare
    28-trigonometry-02 What is greater angle? 1 radians or 1π radians?
  19. Moving
    movie Vojta left the house at three o'clockat 4 km/h. After half hour later went from the same place Filip by bicycle at speed 25 km/h. How long take Tilip to catch up Vojta and how far from the house?
  20. Base
    triangle_2 Compute base of an isosceles triangle, with the arm a=9 cm and a height above the base h=6 cm.

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.