Divisibility + reason - math problems

Number of problems found: 105

  • Lcm = 22 + gcd
    prime The least common multiple of two numbers is 22 more than their greatest common divisor. Find these numbers.
  • We roll
    dices2 We roll two dice A. - what is the probability that the sum of the falling numbers is at most 4 B. - is at least 10 C. - is divisible by 5?
  • Five-digit number
    numbers2 Anna thinks of a five-digit number that is not divisible by three or four. If he increments each digit by one, it gets a five-digit number that is divisible by three. If he reduces each digit by one, he gets a five-digit number divisible by four. If it sw
  • Together
    balls2 The three friends divided the balls in a ratio of 6: 5: 4. Some two of them got a total of 126 balls. How many balls were there together?
  • Coloured numbers
    olympics Mussel wrote four different natural numbers with coloured markers: red, blue, green and yellow. When the red number divides by blue, it gets the green number as an incomplete proportion, and yellow represents the remainder after this division. When it div
  • 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.
  • Divisible by nine
    numbers How many three-digit natural numbers in total are divisible without a remainder by the number 9?
  • How many
    numbers2 How many numbers are less than 222 with a digit sum is 8?
  • Air draft
    numbers2 The numbers 1,2,3,4,5 are written on five tickets on the table. Air draft randomly shuffled the tickets and composed a 5-digit number from them. What is the probability that he passed: and, the largest possible number b, the smallest possible number c, a
  • Columns of two and three
    skola When students in one class stand in columns of two, there is none left. When he stands in columns of three, there is one student left. There are 5 more double columns than three columns. How many students are in the class?
  • Four-digit numbers
    numberline Find four-digit numbers where all the digits are different. For numbers, the sum of the third and fourth digits is twice the sum of the first two digits, and the sum of the first and fourth digits is equal to the sum of the second and third digits. The di
  • Probability
    fractions How probable is a randomly selected three-digit number divisible by five or seven?
  • The florist
    ruze A consignment of 200 roses arrived at the florist in the morning. She sold more than half of them during the day. She wants to tie bouquets of the remaining roses. If she ties a bouquet of three, four, five, or six roses, there will always be one rose lef
  • Integer cube
    cubes2 The length of the cube edge is an integer. Its volume is in cm3 a five-digit number divisible by 1331. What is the length of the edge of this cube.
  • Twenty-five
    prime How many are three-digit natural numbers divisible by 25?
  • Intelligence test
    test Paľo, Jano, Karol, and Rišo were doing an intelligence test. Palo correctly answered half of the questions plus 7 questions, Jano to a third plus 18 questions, Karol to a quarter plus 21 questions and Risho to a fifth plus 25 questions. After the test, Ka
  • By six
    numbers From the digits 1,2,3,4 we create the long integer number 123412341234. .. .. , which will have 962 digits. Is this number divisible by 6?
  • Sum of the digits
    numbers2 How many are two-digit natural numbers that have the sum of the digits 9?
  • Math test
    numbers In mathematics, there were 25 problems of three kinds: light 2 points, medium 3 points, heavy 5 points, the best score is 84 points. How many points did Jane have when she solved all the easy examples, half medium and one-third difficult?
  • Number
    prime What number should be placed instead of the asterisk in number 702*8 to get a number divisible by 6?

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Divisibility - math problems. Reason - math problems.