Prime numbers + natural numbers - math problems

Number of problems found: 141

  • Prime factors
    prime Factor the number 6600 into the product of prime numbers.
  • 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.
  • Primes 2
    prime_table Which prime numbers is number 2025 divisible?
  • Prime factors
    prime Write 98 as a product of prime factors
  • Prime divisors
    plusminus_1 Find 2/3 of the sum's ratio and the product of all prime divisors of the number 120.
  • Count of roots
    eggs How many solutions has equation x. y = 7757 with two unknowns on the set of natural numbers?
  • 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?
  • 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?
  • Rectangles
    rectangles How many rectangles with area 8713 cm2 whose sides are natural numbers are?
  • Year 2018
    new_year The product of the three positive numbers is 2018. What are the numbers?
  • Lcm of three numbers
    prime What is the Lcm of 120 15 and 5
  • 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,
  • Lcm 2
    lcm Create the smallest possible number that is divisible by numbers 5,8,9,4,3
  • MO C–I–1 2018
    numbers_49 An unknown number is divisible by just four numbers from the set {6, 15, 20, 21, 70}. Determine which ones.
  • Common divisors
    prime Find all common divisors of numbers 30 and 45.
  • Z7-I-4 stars 4949
    hviezdicky_mo Write instead of stars digits so the next write of product of the two numbers to be valid: ∗ ∗ ∗ · ∗ ∗ ∗ ∗ ∗ ∗ ∗ 4 9 4 9 ∗ ∗ ∗ ∗ ∗ ∗ 4 ∗ ∗
  • There
    lopticky_2 There are two numbers on the screen - one in the blue and the other in the red box. In the beginning, both numbers are the same. With each beep, both numbers increase - by 1 in the blue field and by 3 in the red field. At one point, the number 49 appears
  • John Smith
    books_1 John Smith is reading a 435-page novel. If he reads the same number of pages per day and the number is a prime number greater than 10, how many pages per day will he read?
  • Numbers
    ten Determine the number of all positive integers less than 4183444 if each is divisible by 29, 7, 17. What is its sum?

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Prime numbers - math problems. Natural numbers - math problems.