Reason + prime numbers - math problems

Number of problems found: 84

  • Six-digit primes
    Find all six-digit prime numbers that contain each one of digits 1,2,4,5,7, and 8 just once. How many are they?
  • The florist
    The florist had 200 roses in the morning. During the day, more than half sold it. From the remaining roses, it will tie the bouquet. If a bouquet of 3, 4, 5, or 6 roses are bound, one always remains. How many roses from the morning shipment sold?
  • Chocolate
    I have a box of chocolate - white, milk and dark. The ratio of white to milk with dark is 3: 4. The ratio of white and milk to dark is 17: 4. Calculate what is the ratio between white, milk, dark chocolate.
  • Four poplars
    Four poplars are growing along the way. The distances between them are 35 m, 14 m, and 91 m. At least how many poplars need to be dropped to create the same spacing between the trees? How many meters will it be?
  • Bricks pyramid
    How many 50cm x 32cm x 30cm brick needed to built a 272m x 272m x 278m pyramid?
  • Year 2018
    The product of the three positive numbers is 2018. What are the numbers?
  • Trees in alley
    There are four trees in the alley between which the distances are 35m, 15m and 95m. Trees must be laid in the spaces so that the distance is the same and the maximum. How many trees will they put in and what will be the distance between them?
  • Hectares
    The tractor plows the first day of 4.5 ha, the second day 6.3 ha, and the third day of 5.4 ha. It worked whole hours a day, and its hourly performance did not change and was the highest of the possible. How many hectares did it plow in one hour (what is i
  • MO C–I–1 2018
    An unknown number is divisible by just four numbers from the set {6, 15, 20, 21, 70}. Determine which ones.
  • Clock's gears
    In the clock machine, three gears fit together. The largest has 168 teeth, the middle 90 teeth, and the smallest 48 teeth. The middle wheel turns around its axis in 90 seconds. How many times during the day do all the gears meet in the starting position?
  • Inverted nine
    In the hotel Inverted Nine, each hotel room number is divisible by 6. How many rooms can we count with the three-digit number registered by digits 1,8,7,4,9?
  • PIN code
    PIN on Michael credit card is a four-digit number. Michael told this to his friend: • It is a prime number - that is, a number greater than 1, which is only divisible by number one and by itself. • The first digit is larger than the second. • The second d
  • Diofant equation
    250x + 120y = 5640
  • 7 digit number
    If 3c54d10 is divisible by 330, what is the sum of c and d?
  • Two rectangles
    I cut out two rectangles with 54 cm², 90 cm². Their sides are expressed in whole centimeters. If I put these rectangles together I get a rectangle with an area of 144 cm2. What dimensions can this large rectangle have? Write all options. Explain your calc
  • Three friends
    Three friends had balls in ratio 2: 7: 4 at the start of the game. Could they have the same number of balls at the end of the game? Write 0, if not, or write the minimum number of balls they had together.
  • School
    Less than 500 pupils attend school. When it is sorted into pairs, one pupil remains. Similarly, when sorted into 3, 4, 5 and 6 members team one remains. Sorted to seven members teams, no left behind. How many pupils are attending this school?
  • Together
    If 8 men, 10 women, 16 children collects ₹1024 in 4 days, how many days will be required for 6 men, 5 women and 4 boys to collect ₹768? (₹ is Indian Rupee)
  • Oranges
    Mother divided her three children's oranges in a ratio of 6:5:4. Two children gave 45 oranges. How many oranges were there?
  • Endless lego set
    The endless lego set contains only 6, 9, 20 kilograms blocks that can no longer be polished or broken. The workers took them to the gym and immediately started building different buildings. And of course, they wrote down how much the building weighed. The

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Reason - math problems. Prime numbers - math problems.