Natural numbers - 9th grade (14y) - math problems

Number of problems found: 153

  • Digits
    numbers2_18 How many natural numbers greater than 4000 which are formed from the numbers 0,1,3,7,9 with the figures not repeated, B) How many will the number of natural numbers less than 4000 and the numbers can be repeated?
  • 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
  • Three-digit
    seven How many three-digit natural numbers do not have the number 7?
  • 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
    numbers_5 How many three-digit natural numbers is greater than 321 if no digit in number repeated?
  • Three-digit integers
    numbers2_49 How many three-digit natural numbers exist that do not contain zero and are divisible by five?
  • Find two
    eq222_7 Find two consecutive natural numbers whose product is 1 larger than their sum. Searched numbers expressed by a fraction whose numerator is the difference between these numbers and the denominator is their sum.
  • Sum of the seventeen numbers
    seq_sum The sum of the 17 different natural numbers is 154. Determine the sum of the two largest ones.
  • Number 4
    numbers_3 Kamila wrote all natural numbers from 1 to 400 inclusive. How many times did she write the number 4?
  • Find the sum
    arithmet_seq_2 Find the sum of all natural numbers from 1 and 100, which are divisible by 2 or 5
  • 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.
  • Rectangles
    rectangle_15 The perimeter of a rectangle is 90 m. Divide it into three rectangles, the shorter side has all three rectangles the same, their longer sides are three consecutive natural numbers. What is the dimensions of each rectangle?
  • A three-digit numbers
    clocks_1 Determine the total number of positive three-digit numbers that contain a digit 6.
  • Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  • Algebrogram
    numbers_26 Solve algebrogram for sum of three numbers: BEK KEMR SOMR ________ HERCI
  • Progression
    sequence_geo_10 -12, 60, -300,1500 need next 2 numbers of pattern
  • Two-digit number
    numbers_1 Digit sum of thinking two-digit natural number is 11. When it exchanging a sequence of digits, given a number which is 27 less than the thinking number. Find out which number I think.
  • 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?
  • Z9–I–1
    ctverec_mo In all nine fields of given shape to be filled natural numbers so that: • each of the numbers 2, 4, 6, and 8 is used at least once, • four of the inner square boxes containing the products of the numbers of adjacent cells of the outer square, • in the cir

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