Grade - examples - page 102

  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. 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?
  3. Body diagonal
    kvadr Cuboid with base 7cm x 3,9cm and body diagonal 9cm long. Find the height of the cuboid and the length of the diagonal of the base,
  4. Letters
    letter The school children have written 20 letters afternoon and then threw 20 letters and then the teacher counted the children and the children were 22 so they went to throw for 2 sheets. How many letters sent together?
  5. 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.
  6. 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?
  7. Four sides of trapezoid
    lichobeznik2 Trapezoid is given by length of four sides: 40.5 42.5 52.8 35.0. Calculate its area.
  8. 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)
  9. Quadratic equation
    Parabola_tangent Quadratic equation ? has roots x1 = 80 and x2 = 78. Calculate the coefficients b and c.
  10. Draw it!
    drawing_geometry Draw two lines c, d that c || d. On line c mark the points A, B. By point A lead perpendicular line to c. By point B lead perpendicular line to c.
  11. 6-gon
    hexagons Perimeter of regular hexagon is 113. Calculate its circumradius (radius of circumscribed circle).
  12. Money borrow
    stur Ms. Kate wants to borrow € 2,000. The company A will borrow ten installments of 240 euros and the first two months does not pay anything. Company B it their position in 12 installments of € 210. Which company has the more favorable interest rate for Ms. K
  13. Square - increased perimeter
    rectangles_4 How many times is increased perimeter of the square, where its sides increases by 150%? If the perimeter of square will increase twice, how much% increases the content area of the square?
  14. 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?
  15. Slope form
    lines_2 Find the equation of a line given the point X(8, 1) and slope -2.8. Arrange your answer in the form y = ax + b, where a, b are the constants.
  16. Copy typist
    pisaci_stroj Typist for 12 hours rewritten 15% of the manuscript. After how many hours he will done 35% of the manuscript?
  17. Holiday SMS
    sms Kucera and Malek start from the holiday together. They agreed that if they be 100 km apart, will send a SMS. Kucera traveling at 60 km/h., Malek 90 km/h. They started at 14 hours PM. At what time they send a message?
  18. Sequence
    sunflower Between numbers 1 and 53 insert n members of the arithmetic sequence that its sum is 702.
  19. Classs mean
    nums Class size is 30 students, math was not worse than sign 2. Determine the number of pupils who were sign 1 if the class had a 1.4 sign average.
  20. Triangle
    triangle_ABC_1 The triangle has known all three sides: a=5.5 m, b=5.3 m, c= 7.8 m. Calculate area of ​this triangle.

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