Examples for 9th grade - page 81

  1. Three cubes
    cubes3 The body was created by gluing three identical cubes. Its volume is 192 cm3. What is its surface in dm2?
  2. Red balls
    gule_3 In the bag there are 3 red, 12 blue and 8 green balls. How many red balls we must be attached to the bag if we want the probability of pulling out the red balls was 20%?
  3. Three friends
    vaha_1 Danica, Lenka and Dalibor have altogether 96 kg. Lenka weighs 75% more than Dalibor and Danica weighs 6 kg more than Dalibor. Determine the weight of Danice, Lenka and Dalibor.
  4. Quotient
    fun1_1 Determine the quotient and the second member of the geometric progression where a3=10, a1+a2=-1,6 a1-a2=2,4.
  5. Diagonals
    koso_uhlopricky Given a rhombus ABCD with a diagonalsl length of 8 cm and 12 cm. Calculate the side length and content of the rhombus.
  6. Coach
    hokej_4 Average age of 24 players and a coach of one team is 24 years. The average age of players without a coach is 23 years. How old is the coach?
  7. Trees
    jablone Along the road were planted 250 trees of two types. Cherry for 60 CZK apiece and apple 50 CZK apiece. The entire plantation cost 12,800 CZK. How many was cherries and apples?
  8. Three granaries
    vaha_3 Three granaries hold 7,800 metric cent (q) of grain. In the first, 70 tonnes of grain was more than the second and in the third it was 120 tonnes less than in the second. How many grain were in each granary?
  9. Two lands
    pozemky The common area of the two neighboring lands is 964 m2. The second land is 77 m2 smaller than twice the size of the first land. Find the areas of each land.
  10. Cross section
    trapezium_right The cross-section ABCD of a swimming pool is a trapezium. Its width AB=14 meters, depth at the shallow end is 1.5 meters and at the deep end is 8 meter. Find the area of the cross-section.
  11. Years
    children_12 Susan is 3 years and as she will be old as Teodor now him will be 11. How old is Teodor today?
  12. Forces on earth directions
    compass2_1 A force of 60 N [North] and 80 N [East] is exerted on an object wigth 10 kg. What is the acceleration of the object?
  13. Conical area
    cones_2 A right angled triangle has sides a=12 and b=19 in right angle. The hypotenuse is c. If the triangle rotates on the c side as axis, find the volume and surface area of conical area created by this rotation.
  14. Hexagon area
    hexagon_1 The center of the regular hexagon is 21 cm away from its side. Calculate the hexagon side and its area.
  15. Q of GP
    geometric_1 Calculate quotient of geometric progression if a1=5 a a1+a2=12.
  16. 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
  17. Cancer
    cancer Of the 80 people 50 people ill cancer. What percentage of people isn't ill?
  18. 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?
  19. Shots
    lopta_5 Determine the percentage rate of keeper interventions if from 32 shots doesn't caught four shots.
  20. Coefficient
    gp Determine the coefficient of this sequence: 7.2; 2.4; 0.8

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