Examples for 8th grade - page 82

  1. Profitability
    zisk The purchase price of goods is 13000, the sales price is the 20000. What is the profitability as a percentage?
  2. Iron cast
    litina What is the weight of cast iron with volume 3575 cubic centimeters. The density of the cast iron is 7600 kg/m3
  3. Ice cream
    zmrzlina Annie likes much ice cream. In the shop are six kinds of ice cream. In how many ways she can buy ice cream to three scoop if each have a different flavor mound and the order of scoops doesn't matter?
  4. Three children
    chocholate_1 3 children eat 8 chocolates in 6 days. How many chocolates 6 children eat in 18 days?
  5. Hydrostatic force
    water3_5 What hydrostatic force is applied to an area of 30 cm2 in water at a depth of 20 m? (Water density is 1000 kg/m3)
  6. Calf
    tela The weight of the calf meat obtained is 65% of the total weight of live calves. What was the weight of a calf from which 285 kg of meat was obtained?
  7. Ace
    esicko The length of segment AB is 24 cm and the point M and N divided it into thirds. Calculate the circumference and area of this shape.
  8. Midpoints
    rovnobeznik_4 Triangle ABC with sides a = 5 cm, b = 3 cm, c = 40mm has a midpoint of K, L, M. How many centimeters is long perimeter of parallelogram KBLM?
  9. Circle r,D
    bavlnka Calculate the diameter and radius of the circle if it has length 52.45 cm.
  10. Kite
    drake_1 John a kite, which is diamond shaped. Its diagonals are 60 cm long and 90 cm long. Calculate: a) the diamond side b) how much paper John needs to make a kite if he needs paper on both sides and needs 5% of the paper for bending.
  11. Wide field
    field The field is 203 meters wide 319 meter long, what is the greater length of the rope by which length and width can be measured and find the exact number of time.
  12. Euros
    bicycles Peter, Jane and Thomas have together € 550. Tomas has 20 euros more than Jane, Peter € 150 less than Thomas. Determine how much has each of them.
  13. Collection
    maliny_1 John has collected half a bucket of raspberries in 45 minutes, Eva collects the whole bucket in an hour. How many minutes it would take to fill a bucket if the two children work together?
  14. Ages
    age2_1 John, Teresa, Daniel and Paul have summary 56 years. Their ages are in a ratio of 1:2:5:6. Determine how many years have each of them.
  15. Metals
    metals_2 In the Hockey World Cup play eight teams, determine how many ways can they win gold, silver and bronze medals.
  16. Inequation
    inequalities Solve the inequation: 5k - (7k - 1)≤ 2/5 . (5-k)-2
  17. Apples in baskets
    basket Determine how many apples are in baskets when in the first basket are 4 apples, and in any other is 29 apples more than the previous, and we have eight baskets.
  18. Family
    family_14 Mom is 42 years old and her daughters 13 and 19. After how many years will mother as old as her daughter together?
  19. Job task
    clocks2_5 After two hours and 40 minutes the job is finished. Compared to last year we were 40 minutes faster. What is the percentage increase to our performance?
  20. Circle's chords
    twochords In the circle there are two chord length 30 and 34 cm. The shorter one is from the center twice than longer chord. Determine the radius of the circle.

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