Examples for secondary school students - page 59

  1. Competition
    sutaz 15 boys and 10 girls are in the class. On school competition of them is selected 6-member team composed of 4 boys and 2 girls. How many ways can we select students?
  2. The gardener
    stromy_3 The gardener bought trees for 960 CZK. If every tree were cheaper by 12 CZK, he would have gotten four more trees for the same money. How many trees did he buy?
  3. Q of GP
    geometric_1 Calculate quotient of geometric progression if a1=5 a a1+a2=12.
  4. Ratio iso triangle
    iso_triangle_2 The ratio of the sides of an isosceles triangle is 7:6:7 Find the base angle to the nearest answer correct to 3 significant figure.
  5. Sum of members
    seq_5 What is the sum of the first two members of the aritmetic progression if d = -4.3 and a3 = 7.5?
  6. Harmonic and arithmetic means
    Plot_harmonic_mean The local Utah Department of Child Service office wants to project staffing needs based on current social worker assignments. They have the number of cases per social worker for the following staff: Mary: 25 John: 35 Ted: 15 Lisa: 45 Anna: 20 Calculat
  7. Right triangle eq2
    rt_triangle_1 Find the lengths of the sides and the angles in the right triangle. Given area S = 210 and perimeter o = 70.
  8. Trapezium ABCD
    lichobeznik_5 In the figure, ABDC is a trapezium in which AB || CD. line segments RN and LM are drawn parallel to AB such that AJ=JK=KP. If AB=0.5m and AP=BQ=1.8m, find the lengths of AC, BD, RN and LM. angle D=angle C=60
  9. Coefficient
    gp Determine the coefficient of this sequence: 7.2; 2.4; 0.8
    math_1 How many words can be created from the word MATEMATIKA by changing the order of the letters, regardless of whether or not the words are meaningful?
  11. Difference AP 4
    sequence_geo_1 Calculate the difference of the AP if a1 = 0.5, a2 + a3 = -1.1
  12. Combinations
    kvadrat_3 If the number of elements increase by 3, it increases the number of combinations of the second class of these elements 5 times. How many are the elements?
  13. Points in plane
    linear_eq_1 The plane is given 12 points, 5 of which is located on a straight line. How many different lines could by draw from this points?
  14. Elements
    fact_1 If the number of elements is decreased by two the number of permutations is decreased 30 times. How many elements are?
  15. Seagull
    cajka Artificially created island in the shape of a circle with a radius of 50 m is overgrown with grass. The only exception is a landing area for helicopters in the shape of a rectangle measuring 15 m and 8 m. What is the probability that the flying seagull (wi
  16. Minimum of sum
    derive_1 Find a positive number that the sum of the number and its inverted value was minimal.
  17. Imaginary numbers
    Complex_conjugate_picture.svg Find two imaginary numbers whose sum is a real number. How are the two imaginary numbers related? What is its sum?
  18. Variation equation
    fun2_4 Solve combinatorics equation: V(2, x+8)=72
  19. Series and sequences
    seq_sum Find a fraction equivalent to the recurring decimal? 0.435643564356
  20. Third member
    seq_6 Determine the third member of the AP if a4=93, d=7.5.

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