Examples for 8th grade - page 24

  1. Money
    hyperinflation Everyone complains about the lack of money. In fact, there is no shortage of money, but the relative scarcity of goods and things that people buy for money. Calculate what percentage of the price of all goods and services rose immediately, if everyone has
  2. Volume from surface area
    cube_3 What is the volume of the cube whose surface area is 96 cm2?
  3. Perpendicular
    perpendicular Determine the slope of the line perpendicular to the line p: y = 9x +7.
  4. Two valves
    pool_2 Water fill the pool by two valves for 16 days. After 6 days the first valve was stopped and the second valve fill pool for 12 days. How many days took to fill the pool each of the valves individually?
  5. Pedestrian
    pedestrian Pedestrian came started at 7h in the morning with speed 3.6 km/h. At half-past eleven cyclist started at 27 km/h same way. How many minutes take cyclist to catch up pedestrian?
  6. Right triangle
    thales_2 Draw a right triangle ABC if |AB| = 5 cm |BC| = 3 cm, |AC| = 4 cm. Draw Thales circle above the hypotenuse of the triangle ABC.
  7. Common chord
    chord2 Two circles with radius 15 cm and 11 cm are intersect at two points. Its common chord is long 20 cm. What is the distance of the centers of these circles?
  8. Fixed expenses 2013
    istoty_komunisti Since 2013, the Slovak government plans to tax more small one person businesses. Instead of fixed expences 40% will be fixed expences 40% of gross income up to 420 Eur. Calculate what percentage of fixed expences will in 2013 pays from gross income 1093 E
  9. Tiles
    dlazdice From how many tiles 20 cm by 30 cm we can build a square of maximum dimensions, if we have maximum 390 tiles.
  10. Five girls
    cats_cicky Five girls traveling by bus. Each holds in each hand two baskets. In each basket are four cats. Each cat has three kittens. Two girls exits bus. How many legs are in the bus?
  11. 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?
  12. Triangular prism
    hranol_3bokovy Calculate the surface area and volume of a triangular prism, base right triangle if a = 3 cm, b = 4 cm, c = 5 cm and height of prism h=12 cm.
  13. Rhombus diagonal
    rhombus2_1 Area of rhombus is 417. One diagonal measures 45, find length of other diagonal.
  14. Semicircle
    tales-de-mileto In the semicircle with center S and the diameter AB is constructed equilateral triangle SBC. What is the magnitude of the angle ∠SAC?
  15. Pine wood
    dre-borovica From a trunk of pine 6m long and 35 cm in diameter with a carved beam with a cross-section in the shape of a square so that the square had the greatest content area. Calculate the length of the sides of a square. Calculate the volume in cubic meters of lum
  16. Train from Prague
    train_cd_1 First train from Prague started at 8:00 hour at 40 kilometers per hour. Train from Ostrava started at 9:20 at 80 km per hour. In how many hours and how far from cities with trains meet if the distance of cities is 400 km.
  17. IS trapezoid
    el_trapezium Isosceles trapezoid arm measured 52 cm. Height is 44 cm and middle segment is 50 cm. Determine length of its bases.
  18. Railway
    train_1 Railway line had on 5.8 km segment climb 9 permille. How many meters track ascent?
  19. Pure quadratic equation
    kvadrat Solve pure quadratic equation ?.
  20. Subway
    metro Subway train went between two stations that gradually accelerated for 20 seconds and reached a speed of 80 km/h. At this rate, went 41 seconds. Then 17 seconds slowed to a stop. What was the distance between the stations?

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.