Natural numbers - examples

  1. 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?
  2. Hens and pigs
    pigs_2 Hens and pigs have 46 feet in total. At least how much can heads have?
  3. Each with each
    tenis_3 Five pupils from 3A class played table tennis. How many matches did they play with each other?
  4. 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,
  5. 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.
  6. 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?
  7. Divide 5
    ratios2 Divide 288 in the following ratio 3 : 4 : 5
  8. Circus
    cirkus On the circus performance was 150 people. Men were 10 less than women and children 50 more than adults. How many children were in the circus?
  9. The Hotel
    hotel-montfort-tatry-2_2 The Holiday Hotel has the same number of rooms on each floor. Rooms are numbered with natural numbers sequentially from the first floor, no number is omitted, and each room has a different number. Three tourists arrived at the hotel. The first one was in r
  10. Six-digit primes
    numberline_1 Find all six-digit prime numbers that contain each one of digits 1,2,4,5,7 and 8 just once. How many are they?
  11. The florist
    ruze_6 The florist had 200 roses in the morning. During the day, more than half sold it. From the remaining roses, it will tie the bouquet. If a bouquet of 3, 4, 5 or 6 roses are bound, one always remains. How many roses from the morning shipment sold?
  12. Three machines
    rozvrh_1 The power of the three machines is 2: 3: 5. Two most powerful machines produce 400 parts per hour. How many components make all three machines in 3 hours?
  13. Chocolate
    cokolada_7 I have a box of chocolate - white, milk and dark. The ratio of white to milk with dark is 3: 4. The ratio of white and milk to dark is 17: 4. Calculate what is the ratio between white, milk, dark chocolate.
  14. Brick
    brick One brick is 6 kg and half a brick heavy. What is the weight of one brick?
  15. Chocolate
    cokolada Randy bought 6 same chocolates for 6 Eur. How many euros will he pay for 25 chocolates?
  16. Divisibility
    divisibility Is the number 761082 exactly divisible by 9? (the result is the integer and/or remainder is zero)
  17. Monkey
    monkey Monkey fell in 38 m deep well. Every day her scramble 3 meters, at night dropped back by 2 m. On that day it gets hangover from the well?
  18. 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
  19. 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
  20. No. of divisors
    triangle_div How many different divisors has number ??

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