Examples for 8th grade - page 26

  1. Two valves
    pool_2 Water fill the pool by two valves for 11 days. After 7 days the first valve was stopped and the second valve fill pool for 7 days. How many days took to fill the pool each of the valves individually?
  2. Ladislav in Amsterdam
    jakob3 Ladislav was reward and went to conference in Amsterdam. Conferense fee was € 3484. Calculate how many books Ladislav could buy at the price of 48 and 52 euros if he don't want fill whole home library and he can buy only 70 books?
  3. Segments
    abs Which of the pairs of numbers on the number line encloses the longest segment: ?
  4. 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 2236 E
  5. Cone
    cones_1 If the segment of the line y = -3x +4 that lies in quadrant I is rotated about the y-axis, a cone is formed. What is the volume of the cone?
  6. Triangle SAA
    triangle_blue The triangle has one side long 71 m and its two internal angles is 60°. Calculate the perimeter and area of the triangle.
  7. Elections
    elections The elections attended a total 4818 voters. First day 39 men more than women, the second day 21 women more than men. How many women attended elections?
  8. Mushrooms
    huby Fresh mushrooms contain 94% water, dried 14%. How many kg of fresh mushrooms is needed to collect to get 10 kg dried?
  9. Leg
    tetris Determine the area of a trapezoid with bases 71 and 42 and height is 4 shorter than the its leg.
  10. Series
    posloupnost_an Andrew wrote this series of numbers: 1,3,7,15, .... n. Which number in the series does not belong? ?
  11. Rhombus diagonal
    rhombus2_1 Area of rhombus is 224. One diagonal measures 33, find length of other diagonal.
  12. Vertical prism
    hranoly3 The base of vertical prism is a right triangle with leg a = 5 cm and a hypotenuse c = 13 cm. The height of the prism is equal to the circumference of the base. Calculate the surface area and volume of the prism
  13. Snowman 2
    snowman_1 On the medal, which has the shape of a circle with a diameter 18 cm is sketched snowman so that the following requirements are met: 1. snowman is composed of three circles, 2. space over snowman is the same as under it, 3. diameters of all circles express
  14. Chord AB
    chord_3 What is the length of the chord AB if its distance from the center S of the circle k(S, 92 cm) is 10 cm?
  15. Hockey players
    players After we cycle five hockey players sit down. What is the probability that the two best scorers of this crew will sit next to each other?
  16. Loan
    loan Apply for a $ 59000 loan, the loan repayment period is 8 years, the interest rate 7%. How much should I pay for every month (or every year if paid yearly). Example is for practise geometric progression and/or periodic payment for an annuity.
  17. Circumscription
    circles43 Calculate radius of the Circumscribed circle in the rectangle with sides 20 and 19. It can be rectangle inscribed by circle?
  18. Pedestrian
    pedestrian Pedestrian came started at 8h in the morning with speed 4.4 km/h. At half-past eleven cyclist started at 26 km/h same way. How many minutes take cyclist to catch up pedestrian?
  19. Chemical parison
    banka_1.JPG The blown parison (with shape of a sphere) have a volume 1.5 liters. What is its surface?
  20. Common chord
    chord2 Two circles with radius 17 cm and 20 cm are intersect at two points. Its common chord is long 27 cm. What is the distance of the centers of these circles?

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