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

  1. Number
    prime What number should be placed instead of the asterisk in number 702*8 to get a number divisible by 6?
  2. No. of divisors
    triangle_div How many different divisors have number ??
  3. Numbers
    ten Determine the number of all positive integers less than 4183444 if each is divisible by 29, 7, 17. What is its sum?
  4. Birthdate
    lizatka Jane on birthday brought 30 lollipops and 24 chewing gum for their friends. How many friends has, if everyone receives the same number of lollipops and chewing gums? How much chewing gum and lollipops got any friend?
  5. Mr. Zucchini
    cuketa Mr. Zucchini had a rectangular garden whose perimeter is 28 meters. Content area of the garden filled just four square beds, whose dimensions in meters are expressed in whole numbers. Determine what size could have a garden. Find all the possibilities and
  6. Plums
    svestka In the bowl are plums. How many would be there if we can divide it equally among 8, 10 and 11 children?
  7. Plumber
    klempir Plumber had to cut the metal strip with dimensions 380 cm and 60 cm to the largest squares so that no waste. Calculate the length of the sides of a square. How many squares cut it?
  8. Seedcake
    pletenky Seedcake costs 44 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros?
  9. LCM
    calc_icon What is the least common multiple of 5, 50, 14?
  10. Rectangles
    rectangles How many rectangles with area 8713 cm2 whose sides is natural numbers are?
  11. Game room
    roulette Winner can took win in three types of jettons with value 3, 30 and 100 dollars. What is minimal value of win payable in this values of jettons?
  12. Divisibility
    dots Determine the smallest integer which divided 11 gives remainder 4 when divided 15 gives remainder 10 and when divided by 19 gives remainder 16.
  13. Lines
    bus Five bus lines runs at intervals 3, 6, 9, 12, 15 minutes. In the morning, suddenly start at 4:00. After how many minutes the bus lines meet again?
  14. Tiles
    kachlicky Hall has dimensions 325 &time; 170 dm. What is the largest size of square tiles that can be entire hall tiled and how many we need them?
  15. School books
    sesity At the beginning of the school year, the teacher distributed 480 workbooks and 220 textbooks. How many pupils could have the most in the classroom?
  16. Count of roots
    eggs How many solutions has equation x. y = 7757 with two unknowns on the set of natural numbers?
  17. Segments
    segments Line segments 62 cm and 2.2 dm long we divide into equal parts which lengths in centimeters is expressed integer. How many ways can we divide?
  18. Tiles
    tiles_1 The room has dimensions 12 m and 5.6 m. Determine the number of square tiles and their largest possible size to cover them room's floor.
  19. Around the flowerbed
    roses Around a rectangular flowerbed with dimensions 5.25 m and 3.5 m are to be planted roses equally spaced so that the roses found in every corner of the flowerbed and consumed them as little as possible. a) At what distance are planted roses? b) How many ros
  20. Racing track
    racing_track On the racing track circling three cars. The first passes one circuit for 8 seconds, the second for 20 seconds and a third for 8 seconds. a) Calculate number of seconds since the start to catch all three cars together for the first time again across the s

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