Examples for 9th grade - page 68

  1. Pears
    hrusky Andrew, Lenka and Rasto have together 232 pears. Lenka has 28 more than Rasto and Rasto pears have 96 more than Andrew. Determine how much each of them has pears.
  2. Cuboid and ratio
    kvader Cuboid has dimensions in ratio 1:2:6 and the surface area of the cuboid is 1000 dm2. Calculate the volume of the cuboid.
  3. Billboard
    rectangle_3 Rectangular billboard is 2.5 m long with a diagonal 2.8 m long. Calculate the perimeter and the content area of the billboard.
  4. Sales of products
    cukriky_9 For 80 pieces of two quality products a total sales is 175 Eur. If the first quality product was sold for n EUR per piece (n natural number) and the second quality product after 2 EUR per piece. How many pieces of the first quality were sold?
  5. Dividing money
    penize_33 Thomas, Honza and Vasek are to divide 1220kč. Honza got 25% more than Thomas. Vasek 20% less than Thomas. How CZK each got?
  6. Class pairs
    pair_1 In a class of 34 students, including 14 boys and 20 girls. How many couples (heterosexual, boy-girl) we can create? By what formula?
  7. Circumscribed circle to square
    kruznice Find the length of a circle circumscribing a square of side 10 cm. Compare it to the perimeter of this square.
  8. Sides ratio
    triangle3_1 Calculate the circumference of a triangle with area 84 cm2 if a:b:c = 10:17:21
  9. Grass
    minutes_clock Peter and Stano lawn grass for 3 hours 12 minutes. How long would it take to Peter if Stano lawn grass himself for 384 minutes.
  10. Midnight
    clocks2_7 How many hours are, if the time that elapsed since 8:00 is 2/5 of the time that will past till midnight?
  11. Largest angle of the triangle
    triangle_1111_2 What is the largest angle of the triangle if the second angle is 10° greater than twice the first and the third is 30° smaller than the second?
  12. Apples 2
    apples_2 How many apples were originally on the tree, if the first day fell one third, the second day quarter of the rest and on tree remained 45 apples?
  13. Principal and interest
    bank_pig Peter put € 270 principal into bank and at the end of the year on account was € 282. To what annual interest rate that Peter had deposited money in the bank?
  14. Hollow sphere
    sphere2 The volume of the hollow ball is 3432 cm3. What is its internal radius when the wall thickness is 3 cm?
  15. Mass
    tubes The thickness of a metallic tube is 1cm and its outer radius is 11cm. Find the mass of such 1m long tube, if the density of the metal is 7.5g per cubic cm.
  16. Barrel 4
    sudy Barrel of water weighs 63 kg. After off 75% water, the weight of the barrel with water is 21 kg. How many kg weigh empty barrel and how many kgs water in it?
  17. Numbers
    primes Write smallest three-digit number, which in division 5 and 7 gives the rest 2.
  18. CuZn
    brass Brass is an alloy of copper and zinc. The 10 centimeter brass cube has a weight of 8.6 kg. Copper density is 8930 kg/m3, the zinc density is 7130 kg/m3. Calculate how many kg of copper and zinc a cube contains.
  19. Reward
    percents_4 Three workers have shared a common reward 13110 CZK follows: first worker got 35% less than the second and third worker got 20% more than the second worker. How much got each worker?
  20. Savings and retirement
    babky_1 The older sibling has saved 44% more euros than the youngest, which represents 22 euros. How many euros older brother has saved ?

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