Grade - examples - page 100

  1. Energy saving
    energy_star They were released three different, independent inventions saving 12%, 15% and 25% energy. Some considered that while the use of these inventions, the total savings will be 12% + 15% + 25% = 52%. Is this true? How much percent of energy will save all thre
  2. Average speed
    earth_2 What is the average speed you have to move the way around the world in 80 days? (Path along the equator, round to km/h).
  3. Pump
    kapka From the pump in the yard dripping water. Every drop is 1 ml. How many drops will be necessary before filling a bucket with a volume of 10 l? Calculate how long it will fulfill the bucket when drops fall each second.
  4. Colour - billboard
    rovnobeznik_1 Shelftalker has the shape of a parallelogram. Its length is 4.9 m and the corresponding height is 3.5 meters. Calculate how much (kg) paint must purchase to redecoration if 1 kg cover 4 m2 of shelftalker surface.
  5. Internal and external angles
    inner_outer_angles_triangle Calculate the remaining internal and external angles of a triangle, if you know the internal angle γ (gamma) = 34 degrees and one external angle is 78 degrees and 40 '. Determine what kind of triangle it is from the size of its angles.
  6. Areaf of ST
    triangle-inside-square It is given square DBLK with side |BL|=13. Calculate area of triangle DKU if vertex U lie on line LB.
  7. Dusan
    parkets a) Dusan break two same window, which has triangular shape with a length of 0.8 m and corresponding height 9.5 dm. Find how many dm2 of glass he needs to buy for glazing of these windows. b) Since the money to fix Dusan has not, must go to the paint job
  8. Cone
    diag22 Into rotating cone with dimensions r = 8 cm and h = 8 cm incribe cylinder with maximum volume so that the cylinder axis is perpendicular to the axis of the cone. Determine the dimensions of the cylinder.
  9. Cube 9
    MD_cheese_cubes What was the original edge length of the cube if after cutting 39 small cubes with an edge length 2 dm left 200 dm3?
  10. Triangle IRT
    triangles_5 In isosceles right triangle ABC with right angle at vertex C is coordinates: A (-1, 2); C (-5, -2) Calculate the length of segment AB.
  11. Alcohol 2
    alko Two types of alcohol one 63% and second 75% give 20 liters of 69% alcohol. How many liters of each type are in the mixture?
  12. Three elephants
    elephant_1 Three elephants eat three piles of hay in 150 minutes. For how long does 96 elephants eat  96 stacks of hay?
  13. Three numbers
    sigma Create from digits 1-9 three-digit numbers with their sum the smallest. What value is the sum of these numbers? (Use each digit only once)
  14. Television
    TV_vintage When we add to the difference between the numbers 1704 and 654 the difference numbers 14920 and 14042, we get a year in which television was invented. How many years people known the TV?
  15. Star
    cross_star Calculate the content of the shaded part of square with side 19 cm.
  16. Quadratic equation
    Parabola_tangent Quadratic equation ? has roots x1 = 80 and x2 = 78. Calculate the coefficients b and c.
  17. Isosceles triangle
    triangles_8 Calculate area and perimeter of an isosceles triangle ABC with base AB if a = 6 cm, c = 7 cm.
  18. Painting school
    painting Redecoration school had scheduled for four crew to 10 days. After two days a single worker ill. For how many days the school was painted when remain workers working with the same tempo?
  19. 6-gon
    hexagons Perimeter of regular hexagon is 113. Calculate its circumradius (radius of circumscribed circle).
  20. Medicine
    lieky We test medicine on 6 patients. For all drug doesn't work. If the drug success rate of 20%, what is the probability that medicine does not work?

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