Natural numbers - problems

  1. 600 pencils
    fixy_2 600 pencils we want to be divided into three groups. The biggest groups have ten pens more than the smallest. How many ways can this be done?
  2. Three numbers
    dices2_9 We have three different non-zero digits. We will create all 3 digits numbers from them to use all 3 figures in each number. We add all the created numbers, and we get the sum of 1554. What were the numbers?
  3. Dozen
    plusminus_13 What is the product of 26 and 5? Write the answer in Arabic numeral. Add up the digits. How many of this is in a dozen? Divide #114 by this
  4. Find the sum
    arithmet_seq_2 Find the sum of all natural numbers from 1 and 100, which are divisible by 2 or 5
  5. Peter and Paul
    clock-night-schr_16 Peter and Paul together have 26 years. Four years ago, Paul was twice older than Peter. How much is Paul and how much Peter?
  6. Voting
    vote_2 400 employees cast their votes in a board member election that has only 2 candidates. 120 people vote for candidate A, while half of the remaining voters abstain. How many votes does candidate B receive?
  7. Hens and pigs
    pigs_2 Hens and pigs have 46 feet in total. At least how much can heads have?
  8. Sum of four numbers
    seq_6 The sum of four consecutive natural numbers is 114. Find them.
  9. Each with each
    tenis_3 Five pupils from 3A class played table tennis. How many matches did they play with each other?
  10. Reminder and quotient
    prime_5 There are given the number C = 281, D = 201. Find the highest natural number S so that the C:S, D:S are with the remainder of 1,
  11. Reminder and quotient
    prime_4 There are given numbers A = 135, B = 315. Find the smallest natural number R greater than 1 so that the proportions R:A, R:B are with the remainder 1.
  12. Collection of stamps
    stamp_11 Jano, Rado, and Fero have created a collection of stamps in a ratio of 5: 6: 9. Two of them had 429 stamps together. How many stamps did their shared collection have?
  13. Brick
    brick One brick is 6 kg and half a brick heavy. What is the weight of one brick?
  14. Chocolate
    cokolada Leslie bought 8 same chocolates for 16 Eur. How many euros will he pay for 25 chocolates?
  15. Divisibility
    divisibility Is the number 761082 exactly divisible by 9? (the result is the integer and/or remainder is zero)
  16. Monkey
    monkey Monkey fell in 23 meters deep well. Every day it climbs 3 meters, at night it dropped back by 2 m. On what day it gets out from the well?
  17. Diophantus
    diofantos_1 We know little about this Greek mathematician from Alexandria, except that he lived around 3rd century A.D. Thanks to an admirer of his, who described his life by means of an algebraic riddle, we know at least something about his life. Diophantus's youth l
  18. Z9-I-4
    numbers_30 Kate thought a five-digit integer. She wrote the sum of this number and its half at the first line to the workbook. On the second line wrote a total of this number and its one fifth. On the third row she wrote a sum of this number and its one nines. Fi
  19. No. of divisors
    triangle_div How many different divisors has number ??
  20. Textbooks
    textbooks After check of textbooks found that every 10-th textbook should be withdrawn. Together 58 textbooks were withdrawn. How many textbooks were in stock before withdrawn and how many after withdrawn?

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