Length - 7th grade (12y) - math problems

Number of problems found: 596

  • 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.
  • The ABCD
    trapezium The ABCD trapezoid has a base length of a = 120mm, c = 86mm and an area of S = 2575 mm2. Calculate the height of the trapezoid.
  • Cube containers
    cubes3 Replace the two cube-shaped containers with 0.8 dm and 0.6 dm edges with a single cube-shaped one so that it has the same volume as the two original ones together. What is the length of the edge of this cube?
  • Volume per time
    inlet How long does fill take for a pump with a volume flow of 200 l per minute fill a cube-shaped tank up to 75% of its height if the length of the cube edge is 4 m?
  • Square gardens
    zahrada The gardening colony with dimensions of 180 m and 300 m is to be completely divided into equally large square areas with the largest possible area. Calculate how many such square areas can be obtained and determine the side length of the square.
  • 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?
  • Pegs
    meter 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?
  • Bricks
    bricks How many bricks are needed for a wall 14.5 m long, 2 m high and 45 cm thick, if 285 bricks are needed for one m ^ 3 wall?
  • Nautical miles
    mapa How many nautical miles do they sail if the route is shown on a 1:25 000 scale map with a 7.4 cm long line?
  • Roof repair
    wood To repair the roof, we need 15 pieces of boards 6 m long, 15 cm wide and 25 mm thick. How many euros will we pay for all boards if 1 m3 of boards costs 500 euros?
  • Isosceles trapezoid
    rr_lichobeznik Find the area of an isosceles trapezoid with bases of 8cm and 72mm. The height of the trapezoid is equal to three-quarters of the longer base.
  • A cliff
    cliff A line from the top of a cliff to the ground passes just over the top of a pole 5 ft high and meets the ground at a point 8 ft from the base of the pole. If the point is 93 ft from the base of the​ cliff, how high is the​ cliff?
  • 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?
  • Two villages
    mapa Two villages are 11 km and 500 m away. On the map, their distance is determined by a 5 cm long line. Find the scale of the map.
  • The string
    string They cut 113 cm from the string and divided the rest in a ratio of 5: 6.5: 8: 9.5. The longest part measured 38 cm. Find the original length of the string.
  • Extending square garden
    garden_el Mrs. Petrová's garden had the shape of a square with a side length of 15 m. After its enlargement by 64 m2 (square), it had the shape of a square again. How many meters has the length of each side of the garden been extended?
  • Gears
    bicycle_gears The front gear on the bike has 32 teeth and the rear, on the wheel, has 12 teeth. How many times does the bike's rear-wheel turn if you turn the right pedal 30 times? What distance will you go if the circumference of the bicycle wheel is 250 cm?
  • Poplar shadow
    shadow The nine-meter poplar casts a shadow 16.2 m long. How long does a shadow cast by Peter at the same time, if it is 1.4 m high?
  • Height
    triangle_rt1 The content of the triangle is 35 cm2. The length of the base is 10 cm. Determine the length of the height on the base.
  • Chimney and tree
    shadow Calculate the height of the factory chimney, which casts a shadow 6.5 m long in the afternoon. At the same time, a 6 m high tree standing near it casts a shadow 25 dm long.

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Do you want to convert length units? Length - math problems. Examples for 7th grade (seventh).