Natural numbers - 7th grade (12y) - math problems

Number of problems found: 160

  • Aman
    clocks2_1 Aman, Anna and Tina are participating in the school race. Anna completes a lap in 120 minutes, Aman completes a lap in 240 minutes and Tina completes a lap in 60 minutes. If they all started at the same time, then after how long will they meet again?
  • You have
    sane You have 4 reindeer and you want to have 3 fly your sleigh. You always have your reindeer fly in a single-file line. How many different ways can you arrange your reindeer?
  • 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.
  • Drivers
    clocks2 Driver Franta and driver Karel are friends. They leave the start-stop both at the same time in the afternoon - at 13.30. When will they meet again if Franta goes around his route in 50 minutes and Karel in 40 minutes?
  • Remainder
    dice What is the remainder of the division of natural numbers 293 and 7?
  • Divisible by nine
    numbers_2 How many three-digit natural numbers in total are divisible without a remainder by the number 9?
  • The sum
    eq1 The sum of five consecutive odd numbers is 75. Find out the sum of the second and fourth of them.
  • Library
    books_1 New books were purchased for the library. Five-eighths were professional books, one-fifth were encyclopedias, and 231 books were dictionaries. How many professional books were there?
  • Sum of seven
    numbers_5 The sum of seven consecutive odd natural numbers is 119. Determine the smallest of them.
  • Ratio
    maliny Alena collected 7.8 kg of blueberries, 2.6 kg of blackberries, and 3.9 kg of cranberries. Express the ratio in the smallest natural numbers in this order.
  • Three ships
    ship There are three ships moored in the port, which sail together. The first ship returns after two weeks, the second after four weeks, and the third after eight weeks. In how many weeks the ships will meet in the port for the first time? How many times have
  • Largest squares
    metals How many of the largest square sheets did the plumber cut the honeycomb from 16 dm and 96 dm?
  • Dance ensembles
    dancers 4 dance ensembles were dancing at the festival. None had less than 10 and more than 20 members. All dancers from some of the two ensembles were represented in each dance. First, 31 participants were on the stage, then 32, 34, 35, 37, and 38. How many danc
  • Find the mean
    mean_normal Find the number between 13 and 29.
  • How many
    numbers2_3 How many numbers are less than 222 with a digit sum is 8?
  • Pegs
    meter_1 From two sticks 240 cm and 210 cm long, it is necessary to cut the longest possible pegs for flowers so that no residues remain. How many pegs will it be?
  • Prime factors
    prime Factor the number 6600 into the product of prime numbers.
  • Three
    bus27_1 Three buses follow the same circular route. The first driver is the slowest because he has many stops, and it takes him 90 minutes to cross the route. The second driver will pass the circuit in 1 hour. The third driver has the fewest stops, and the circui
  • 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?
  • Games
    chess Jack and Paul decided to play chess against each other. They bet ten pesos on each game they played. Jack won three bets and Paul won fifty pesos. How many games did they play?

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