Natural numbers - 8th grade (13y) - math problems

Number of problems found: 157

  • Unknown numbers
    eq222_3 The sum of two consecutive natural numbers and their triple is 92. Find these numbers.
  • Big numbers
    numbers_1 How many natural numbers less than 10 to the sixth can be written in numbers: a) 9.8.7 b) 9.8.0
  • AM of three numbers
    arithmet_seq The number 2010 can be written as the sum of 3 consecutive natural numbers. Determine the arithmetic mean of these numbers.
  • Three-digit
    seven How many three-digit natural numbers do not have the number 7?
  • Count of roots
    eggs How many solutions has equation x. y = 7757 with two unknowns on the set of natural numbers?
  • Sum of seven
    numbers_5 The sum of seven consecutive odd natural numbers is 119. Determine the smallest of them.
  • Three-digit integers
    numbers2_49 How many three-digit natural numbers exist that do not contain zero and are divisible by five?
  • Twenty-five
    prime How many three-digit natural numbers are divisible by 25?
  • Rectangles
    rectangles How many rectangles with area 8713 cm2 whose sides are natural numbers are?
  • Two numbers 7
    numbers_49 The sum of two consecutive even numbers is 30. Find the numbers.
  • 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?
  • Telephone numbers
    phones How many 7-digit telephone numbers can we put together so that each number consists of different digits?
  • Odd numbers
    friends4_2 The sum of four consecutive odd numbers is 1048. Find those numbers ...
  • Three-digit numbers
    numbers_2 We have digits 0,1,4,7 that cannot be repeated. How many three-digit numbers can we write from them? You can help by listing all the numbers.
  • Three numbers
    dices2_9 We have three different non-zero digits. We will create all 3 digits numbers from them to use all 3 figures in each number. We add all the created numbers, and we get the sum of 1554. What were the numbers?
  • How many
    numbers2_41 How many double-digit numbers greater than 30 we can create from digits 0, 1, 2, 3, 4, 5? Numbers cannot be repeated in a two-digit number.
  • Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  • Even / odd numbers
    parne_neparne a / Using variable n write two consecutive odd numbers. b / the sum of three consecutive odd numbers is 333. What are this numbers?
  • A three-digit numbers
    clocks_1 Determine the total number of positive three-digit numbers that contain a digit 6.
  • Drawing from a hat
    klobouk When drawing numbers from a hat from 1 to 35, we select random given numbers. What is the probability that the drawn numbers will be divisible by 8 and 2?

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