Prime numbers - math problems

Number of problems found: 222

  • Prime factors
    prime Factor the number 6600 into the product of prime numbers.
  • Primes 2
    prime_table Which prime numbers is number 2025 divisible?
  • 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.
  • Decomposition
    prime_factorization Make decomposition using prime numbers of number 155. Result write as prime factors (all, even multiple)
  • Prime factors
    prime Write 98 as product of prime factors
  • Prime divisors
    plusminus_1 Find 2/3 of the ratio of the sum and the product of all prime divisors of the number 120.
  • Prime number
    prime_2 Jan wrote any number from 1 to 20. What is the probability that he wrote the prime number?
  • 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?
  • Unknown number
    unknown Unknown number is divisible by exactly three different primes. When we compare these primes in ascending order, the following applies: • Difference first and second prime number is half the difference between the third and second prime numbers. • The prod
  • Raffle
    tombola_tickets In the pool is numbers from 1 to 115. What is the probability that a randomly selected number is not a prime number?
  • Amazing number
    numbers4 An amazing number is name for such even number, the decomposition product of prime numbers has exactly three not necessarily different factors and the sum of all its divisors is equal to twice that number. Find all amazing numbers.
  • Year 2018
    new_year The product of the three positive numbers is 2018. What are the numbers?
  • Jhon Regand
    books_1 Jhon Regand 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?
  • Common divisors
    prime Find all common divisors of numbers 30 and 45.
  • The tickets
    oriesky The tickets to the show cost some integer number greater than 1. Also, the sum of the price of the children's and adult tickets, as well as their product, was the power of the prime number. Find all possible ticket prices.
  • Lcm of three numbers
    prime What is the Lcm of 120 15 and 5
  • Twenty-five
    prime How many are three-digit natural numbers divisible by 25?
  • Fractions
    cmp_fractions Sort fractions ? by its size. Result write as three serial numbers 1,2,3.
  • Lcm 2
    lcm Create the smallest possible number that is divisible by numbers 5,8,9,4,3
  • Count of roots
    eggs How many solutions has equation x. y = 7757 with two unknowns on the set of natural numbers?

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