Multiplication - high school - math problems

  1. Uboid volume
    cuboid Calculate the cuboid volume if the walls are 30cm², 35cm², 42cm²
  2. Cube construction
    222cube A 2×2×2 cube is to be constructed using 4 white and 4 black unit cube. How many different cubes can be constructed in this way? ( Two cubes are not different if one can be obtained by rotating the other. )
  3. Boys and girls
    dancers There are 20 boys and 10 girls in the class. How many different dance pairs can we make of them?
  4. Lathe
    sustruh 95% of the components manufactured on the lathe comply with the standard, of which 80% of the components are first-class. How likely can we expect a manufactured part to be first class?
  5. Percent change
    rectangles If the length of a rectangle is increased by 25% and the width is decreased by 10%, the area of the rectangle is larger than the area of the original rectangle by what percent?
  6. Bookshelf and books
    bookshelf How many can we place 7 books in a bookshelf?
  7. Scalar product
    vectors_sum0_2 Calculate the scalar product of two vectors: (2.5) (-1, -4)
  8. Practice
    telocvik How many ways can you place 20 pupils in a row when starting on practice?
  9. Odd/even number
    numbers2_49 Pick any number. If that number is even, divide it by 2. If it's odd, multiply it by 3 and add 1. Now repeat the process with your new number. If you keep going, you'll eventually end up at 1. Every time. Prove. ..
  10. How many 2
    chart_2 How many three lettered words can be formed from letters A B C D E G H if repeats are: a) not allowed b) allowed
  11. Mixed with percentages
    percent_21 Calculate 33 1/3% of 570.
  12. Progression
    sequence_geo_10 12, 60, -300,1500 need next 2 numbers of pattern
  13. Fruit tea
    tea_3 Tea contains 7% of fruit components and 12% of sugar in this component. How many percents of sugar is represented in the whole tea?
  14. Associative law multiplication
    sale_4 In a warehouse, you obtain a 20% discount but you must pay a 15% sales tax. Which would you prefer to have calculated first: discount or tax? Explain. (result write as: 1 = first discount, 2 = first tax, 3 = no matter what first)
  15. Points collinear
    collinear Show that the point A(-1,3), B(3,2), C(11,0) are col-linear.
  16. Rate or interest
    penize_45 At what rate percent will Rs.2000 amount to Rs.2315.25 in 3 years at compound interest?
  17. 3 years savings
    penize_35 Simple interest - Tereza has deposited CZK 100,000 in the bank with an annual interest rate of 1.5%. Interest is added each year and left aside. How many CZK crowns will has total after 3 years?
  18. Math logic
    children_7 There are 20 children in the group, each two children have a different name. Alena and John are among them. How many ways can we choose 8 children to be among the selected A) was John B) was John and Alena C) at least one was Alena, John D) maximum one w
  19. Bookshelve
    money_15 Bookshelve with an original price of € 200 twice become cheaper. After the second discounted by 15% the price was € 149.60. Determine how much % become cheaper for the first time.
  20. Eight palm
    palma There grows 8 palms by the sea. At the first sitting one parrot, on second two, on third sits four parrots on each other twice the previous parrots sitting on a previous palm. How many parrots sitting on eighth palm?

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