Examples for 9th grade - page 72

  1. Copper parts
    bulb2_3 From copper cast were made 3 parts. At first consumed one third of casting, the second 2/3 of rest and the third weighed 18 kg. What is the weight of original copper cast?
  2. 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?
  3. Three children
    chocholate_1 3 children eat 8 chocolates in 6 days. How many chocolates 6 children eat in 18 days?
  4. 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.
  5. Average
    chart If the average(arithmetic mean) of three numbers x,y,z is 50. What is the average of there numbers (3x +10), (3y +10), (3z+10) ?
  6. Water wessel
    karafa The vessel containing water has a weight 19 kg. After pouring half the water its weigth 11 kg. What is the weight of the empty vessel?
  7. 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.
  8. Repair company
    servis The company repairs cars. The first day repair half of the contract second day, the half of the rest and third day 6 residue cars. How many total cars company repaired?
  9. Hockey match
    football_2 The hockey match ended with result 3:1. How many different storylines may have the match?
  10. Alcohol mixture
    roztoky_1 From 55% and 80% alcohol we have to produce 0.2 kg of 60% alcohol. How many of them do we use in solution?
  11. Threesome
    3friends_1 Dana, Dalibor and Michael have a combined 57 years. Dana is five years older than Dalibor, but Dana is five years younger than Michael. Determine how old is Dana, Dalibor and Michael.
  12. 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?
  13. Reciprocal equation
    img_reci_1 Determine the root of the equation: 9/x-7/x=1
  14. Fit ball
    fitball What is the size of the surface of Gymball (FIT - ball) with a diameter of 65 cm?
  15. Fertilizer
    luka_1 Meadow with an area of 1,500 square meters was fertilized with 12 kg of urea. Urea contains 45% nitrogen. How much nitrogen accounted per 1 m2?
  16. Cone
    valec_8 The rotating cone volume is 9.42 cm3, with a height 10 cm. What angle is between the side of the cone and its base?
  17. Apples 2
    jablka_6 Dried apples contain 15% water. Fresh apples contain 80% water. How many kg of apples we need buy in order to get 3 kg of dried apples?
  18. Linear function
    intersection_fn_1 What is the equation of linear function passing through points: a) A (0,3), B (3,0) b) A (-2,-6), B (3,4)
  19. Banknotes
    ducat $ 1390 was collected. How much was in $20 notes and how many in $50 notes in that order? How many solutions exists?
  20. Electricity consumption cost
    Temelin4veze1 Last year Karol family reduced its electricity consumption by 31% compared to the previous year and paid CZK 2883 less. How many CZK is electricity last year and how many two year ago?

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