Least common multiple (LCM) - math problems

Number of problems found: 122

  • A number 5
    numbers A number is divisible by 24, 25, and 120 if it is increased by 20. Find the number.
  • The drama club
    cinema The drama club meets in the auditorium every 6 days and the choir meets there every 5 days. If the groups are both meeting in the auditorium today, then how many days from now will they next have to share the auditorium?
  • A rope
    meter A rope can be cut into equal length with no rope left over. The lengths can be 15cm,18cm or 25cm. What is the shortest possible length of the rope?
  • Per shift
    time Two cars take beets from the same field to the sugar factory. Both drive at the same average speed. A car with mechanical tipping needs 15 minutes to travel to the sugar factory and back. A car that does not have a mechanical tipping needs 6 minutes longe
  • Lcm to eliminate y
    eq2_fx Identify the least common multiple that would eliminate the y-variable. 6x - 5y = -4 4x + 2y = 28
  • Find unknown number
    numbers What is the number between 50 and 55 that is divisible by 2,3,6,9?
  • Coloured numbers
    olympics Mussel wrote four different natural numbers with coloured markers: red, blue, green and yellow. When the red number divides by blue, it gets the green number as an incomplete proportion, and yellow represents the remainder after this division. When it div
  • Two hundred
    sportka Two hundred ten athletes competed in three athletics races on three fields. One hundred five athletes competed in the first, 60 in the second, and everyone else in the third. On the individual courts, the athletes were divided into groups. Each group, alt
  • The classroom
    meter The classroom is 9 meters long. The width of the classroom is smaller and can be passed in equally long steps of 55 CM or 70 CM. Determine the width of the classroom.
  • Aman
    clocks2 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?
  • Summer camp
    tablo Some boys or girls signed up for the summer camp, which has a maximum capacity of 200 children. The main leader noticed that during the evening start, he could arrange the participants exactly in the twelve-step, sixteen-step, or eighteen-step, and no one
  • Tractor wheels
    tractor The front wheel of the tractor has a circumference of 18 dm and the rear 60 dm. We will make a red mark on the lowest point of both wheels. The tractor then starts. At what distance from the start will both marks appear identically at the bottom again?
  • Three
    bus27 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
  • Two gears
    gears-3 Two gears with 13 and 7 teeth rotate locked into each other. How many turns does a big wheel have to make for both wheels to be in the starting position again?
  • 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
  • Lamps on playground
    lamp The playground has the shape of a rectangle 36 x 50m. After how many meters will he place the lamps on his lighting, if the distances between them are to be the same on both sides if the builders want to use the smallest possible number of lamps?
  • 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.
  • On a
    venusa On a some day, the Sun, Venus and the Earth are in eclipse, i. E. Venus is between the Sun and the Earth. Venus orbits the Sun in 225 days. In how many years will all three bodies be in alignment again?
  • 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?
  • Tram stop
    elektricka The blue tram stops every 12 minutes, the red one 8 minutes. At 8 o'clock they left the stop together. How many times do they meet at a stop before 11 am?

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