Natural numbers - problems

  1. Two buses
    bus27_14 The first bus runs 15 minutes the second bus runs after 21 minutes. Together they both leave at 7:00 on Monday. When and what day will they meet?
  2. Container
    cubes3_9 The container-shaped box with internal dimensions of 3.9 m, 3.25 m and 2.6 m was completely filled with goods in the same cubic boxes. How long edge could this box have?
  3. Written number
    numbers2_49 Place+values x ten thousands =30 thousands
  4. Minimum surface
    cuboid_20 Find the length, breadth, and height of the cuboid shaped box with a minimum surface area, into which 50 cuboid shaped blocks, each with length, breadth and height equal to 4 cm, 3 cm and 2 cm respectively can be packed.
  5. Diofant equation
    eq222_19 250x + 120y = 5640
  6. Maria
    green-grapes Maria has decided to plant grapes in the garden behind her house. His neighbor Ben has grown grapes successfully for a long time and has given Maria advice on how to plant vines. Ben told her to plant them 3 meters apart in rows that are also 3 meters apar
  7. My father
    tree3_2 My father has a big farm. 6/8 of it were planted with mango trees, 1/2 of the remainder are guava trees and the rest 10 trees are santol trees. What is the number of all trees?
  8. Factors 2
    powers_2 A number has 3 identical factors. If 1 of them is 18. Find the number step by step
  9. To improve
    one_2 To improve her handwriting Paula practices writing the numbers 1 to 200 in words. How many times will she have written the word "one" in all?
  10. Counting number
    numbers2_49 What is the smallest counting number divisible by 2,5,7,8 and 15?
  11. Sum of two primes
    prime_1 Christian Goldbach, a mathematician, found out that every even number greater than 2 can be expressed as a sum of two prime numbers. Write or express 2018 as a sum of two prime numbers.
  12. 7 digit number
    numbers2_49 If 3c54d10 is divisible by 330, what is the sum of c and d?
  13. Brick
    brick One brick is 6 kg and half a brick heavy. What is the weight of one brick?
  14. Chocolate
    cokolada Randy bought 6 same chocolates for 6 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 32 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?
  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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