Divisibility + natural numbers - math problems

Number of problems found: 127

  • Divisibility 2
    divisors How many divisors have integer number 13?
  • Divisibility
    nice_circles Determine all divisors of number 84.
  • All pairs
    cisla Determine all pairs (m, n) of natural numbers for which is true: m s (n) = n s (m) = 70, where s (a) denotes the digit sum of the natural number a.
  • Count of roots
    eggs How many solutions has equation x. y = 7757 with two unknowns on the set of natural numbers?
  • Three-digit integers
    numbers2_49 How many three-digit natural numbers exist that do not contain zero and are divisible by five?
  • Divisible by nine
    numbers_2 How many three-digit natural numbers in total are divisible without a remainder by the number 9?
  • Twenty-five
    prime How many are three-digit natural numbers divisible by 25?
  • Sum of the digits
    numbers2 How many are two-digit natural numbers that have the sum of the digits 9?
  • Rectangles
    rectangles How many rectangles with area 8713 cm2 whose sides are natural numbers are?
  • Digit sum
    numbers_19 Find the smallest natural number n, the digit sum of which is equal to 37.
  • Seven numbers
    numbers Write seven 4-digit numbers that are divisible by 3 and at the same time by 4.
  • Theorem prove
    thales_1 We want to prove the sentence: If the natural number n is divisible by six, then n is divisible by three. From what assumption we started?
  • How many 4
    numbers2_1 How many 4 digit numbers that are divisible by 10 can be formed from the numbers 3, 5, 7, 8, 9, 0 such that no number repeats?
  • 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,
  • Divisibility
    dots Determine the smallest integer which divided 11 gives remainder 4 when divided 15 gives remainder 10 and when divided by 19 gives remainder 16.
  • How many
    numbers2_3 How many numbers are less than 222 with a digit sum is 8?
  • Odd numbers
    friends4_2 The sum of four consecutive odd numbers is 1048. Find those numbers ...
  • Primes 2
    prime_table Which prime numbers is number 2025 divisible?
  • Year 2018
    new_year The product of the three positive numbers is 2018. What are the numbers?
  • Three digits number
    3digit From the numbers 1, 2, 3, 4, 5 create three-digit numbers that digits not repeat and number is divisible by 2. How many numbers are there?

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Divisibility - math problems. Natural numbers - math problems.