Reason - 9th grade (14y) - math problems

Number of problems found: 504

  • Apple collecting
    jablka Luke, Peter and Tibor compared how many kilograms of apples they had collected. They found that the arithmetic mean of what Luke and Peter collected was 10 kg larger than Tibor's contribution, and the arithmetic mean of what Luke and Tibor collected was 3
  • Gas prices 2021
    gasprom According to the SPP price list in 2021, the price of natural gas together with its supply is as follows: D1 - we cook. Fix 3.34 euros/month and 0.0479 euros/kWh (1 cubic meter of gas is approximately 10.555 kWh. It is called combustion heat and changes o
  • Two numbers
    eq1 One number is by 79 larger than the other. If we divide the larger number by the smaller one, we get the ratio 5 and the remainder 11. Determine both numbers.
  • Strawberries
    jahoda Three people pick strawberries from 48 rows in 8 hours. How many hours do five people need to pick strawberries from 20 rows?
  • The vaccination
    covid19 The vaccination coverage of the population is 80%. Unvaccinated make up 60% of all infected. What percentage are unvaccinated more likely to be infected?
  • Cost structure
    factory_butter You are currently trying to decide between two cost structures for your business: one that has a greater proportion of short-term fixed costs and another that is more heavily weighted to variable costs. Estimated revenue and cost data for each alternative
  • Boys and girls 8
    boy In a class of 35 boys and girls that has a ratio of 2:5, 5 boys are absent and 5 boys are present. How many students are present?
  • In the library
    books In the library at Lenape Elementary School, there are 2/5 as many fiction books as there are nonfiction books. There are 56 books in the school library. How many books are fiction books?
  • Maria 2
    family Maria is 7 years older than her brother Robert and in 2 years her age will be four times what Robert’s age was three years ago. Find their present ages.
  • Special sequence
    seq What if            2×9=1            3×9=2            4×9=3            5×9=4            6×9=5            7×9=6            8×9=7            9×9=8           10×9=9    then 1×9=??? answer with solutions. .. ..
  • Wheel gear
    bicycle_gears A drive wheel of radius 2 is connected to a drive wheel of radius 1 by a pulley of length 17. What is the distance between the wheel axles?
  • Petra's test
    test The answer will be given 8 marks, and the wrong answer will be deducted 3 marks. The total number of marks obtained by the school is 36. If Petra answered six questions correctly,   how many questions were answered incorrectly by the student from the scho
  • Smoker male
    venn_intersect For a person selected randomly from a certain population, events A and B are defined as follows. A = event the person is male B = event the person is a smoker. For this particular population, it is found that P(A ) = 0.53, P(B) = 0.15, and P(A n B ) = 0.1
  • Three towns and roads
    map If there are 3 roads from town A to town B And 4 roads from town B to town C, in how many ways can one go from town A to town C and back to town A, through town B, without passing through the same road twice?
  • Hockey Championships
    hokej At the 2021 World Hockey Championships, there are eight teams in Group A, each of which plays seven matches. There are 4 points for each team to gain points (3-2-1-0), but it is always paired with the opponent's points ( 0-1-2-3). How many points are ther
  • Three subjects
    venn In a class of 40 students, 18 passed mathematics, 19 passed accounts, 16 passed economics, 5 mathematics and accounts only, 6 mathematics only, 9 accounts only, 2 accounts and economics only, if each student offered at least one of the subjects. a) how ma
  • A married
    family A married couple planned to have 3 children. i. List the possible combinations of the sexes of 3 children. Use B for boy and G for girl. ii. Calculate the probability that all three children would be of the same gender
  • Gym center
    sale 80% of all visitors to the gym center enjoy a discount. 3/4 of all visitors go to practice regularly. All visitors who go to the gym regularly benefit from a discount. What percentage of all visitors do not go to the gym regularly but still use the discou
  • The carpenters
    wood The carpenters cut the beam. Half of the cut pieces were 1 meter long, a quarter of the pieces were two meters long and the remaining 8 meters of the beam were cut into two equal parts. - What was the length of the original beam? - What part of the origin
  • Two-digit number
    numbers In a two-digit number, the number of tens is three greater than the number of units. If we multiply the original number by a number written in the same digits but in reverse order, we get product 3 478. Find the original number.

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Reason - math problems. Examples for 9th grade.