Natural numbers - examples

  1. Three-digit
    seven How many three-digit natural numbers do not have the number 7?
  2. Digits
    numbers_48 How many five-digit numbers can be written from numbers 0.3,4, 5, 7 that is divided by 10 and if digits can be repeated.
  3. Wide field
    field The field is 203 meters wide 319 meter long, what is the greater length of the rope by which length and width can be measured and find the exact number of time.
  4. Lcm of three numbers
    prime What is the Lcm of 120 15 and 5
  5. Brick
    brick One brick is 2 kg and half a brick heavy. What is the weight of one brick?
  6. Chocolate
    cokolada Charlie bought 7 same chocolates for 14 Eur. How many euros he pay for 27 chocolates?
  7. Divisibility
    divisibility Is the number 109433 divisible by 7?
  8. Monkey
    monkey Monkey fell in 31 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?
  9. 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
  10. 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
  11. Textbooks
    textbooks After check of textbooks found that every 8-th textbook should be withdrawn. Together 74 textbooks were withdrawn. How many textbooks were in stock before withdrawn and how many after withdrawn?
  12. No. of divisors
    triangle_div How many different divisors has number ??
  13. Numbers
    ten Determine the number of all positive integers less than 2937474 if each is divisible by 11, 23, 17. What is its sum?
  14. Steps
    square_diagonal_1 How many steps you save if you go square estate for diagonal (crosswise), rather than circumvent on the two sides of its perimeter with 298 steps.
  15. Weeks
    calendar 55 weeks is equal to how many days?
  16. Camp
    skauti In the camp are children. 1/4 went on a trip, 1/2 went to bathe and 99 children remained in the room. How many children are in camp?
  17. Cherries
    visne Cherries in the bowl can be divided equally among 11 or 16 or 4 children. How many is the minimum cherries in the bowl?
  18. Z9–I–1
    ctverec_mo In all nine fields of given shape to be filled natural numbers so that: • each of the numbers 2, 4, 6 and 8 is used at least once, • four of the inner square boxes containing the products of the numbers of adjacent cells of the outer square, • in the cir
  19. Camel
    camels Camel owner wants to get out of the city into oasis. He bought 3000 bananas, which wants to sell in oasis. However oasis from the city divided 1,000 kilometers of desert. Camel can carry at one time up to 1000 bananas, and for every kilometer traveled, ea
  20. Balls
    balls I have 12 balls and my friend has 18. About how many has my friend more balls?

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