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

Number of problems found: 331

  • 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?
  • Divide in ratio
    lines_2 Line segment AB 12 cm long divide in a ratio of 5: 3. How long are the individual parts?
  • A section
    boardwalk A section of the boardwalk is made of 15 boards. Each board is 9 1/4 inches wide. The total width of the boardwalk is 144 inches. The spacing between each board is equal. What is the width of the spacing between the boards?
  • Gears
    bicycle_gears_2 The front gear on the bike has 32 teeth and the rear, on the wheel, has 12 teeth. How many times does the rear wheel of the bike turns if you turn the right pedal 30 times? What distance will you go if the circumference of the bicycle wheel is 250 cm?
  • Length of the arc
    obluk What is the length of the arc of a circle k (S, r=68mm), which belongs to a central angle of 78°?
  • Cuboid walls
    watertank The base of the block is a rectangle whose sides have lengths in the ratio 13: 7. Find the volume of the block in liters, if the longer side of the base measures 65 cm and the height of the block is 1.2 m
  • Winch drum
    bubon Originally an empty winch drum with a diameter of 20 cm and a width of 30 cm on the rescue car, he started winding a rope with a thickness of 1 cm beautifully from edge to edge. The winch stopped after 80 turns. It remains to spin 3.54m of rope (without h
  • The plan
    city The plan of the housing estate is in three scales 1: 5000,1: 10000,1: 15000. The distance between two points on a plan with a scale of 1: 10000 is 12 cm. What is this distance on the other two plans? What is this distance?
  • Identical cubes
    cubes3 From the smallest number of identical cubes whose edge length is expressed by a natural number, can we build a block with dimensions 12dm x 16dm x 20dm?
  • Used cars
    renault Peter plans to buy a used car: the first car Renault Espace 2.0 dCi 16V Dynamique 2006, costs 2000 euros. It is 14 years old and has a combined diesel consumption of 8 liters. / 100 km. Diesel costs 1.1 euros/liter. How much will the car cost him to opera
  • The tourist
    tourist The tourist walked a quarter of the way on the first day, a third of the rest on the second day, and 20 km on the last day. How many km did he walk in three days?
  • Flowerbeds
    meter_24 What is the smallest length of flowerbeds we have to prepare to plant seedlings at grid 20,30,25,40 cm?
  • Iron pole
    pole The iron pole is in the ground 2/5 of its length, partly above the ground 1/3 is yellow, and the unpainted section is 6 m long. How long is the entire column?
  • Let x
    rectangle Let x represent one quantity. State what that quantity represents. Express the second quantity in terms of x. The length of the rectangle is 4 inches less than 8 times the width.
  • Poplar shadow
    shadow_1 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?
  • Two ribbons
    meter_1 The total length of the two ribbons is 13 meters. If one ribbon is 7 and 5/8 meters long, what is the length of the other ribbon?
  • A sculptor
    statue A sculptor is duplicating a statue based on an original statue. If the scale factor of the replication is 3.2, will the new statue be larger or smaller than the original statue (enter 1 = larger, 0= smaller)
  • Cube into cylinder
    cube_sphere_in If we dip a wooden cube into a barrel with a 40cm radius, the water will rise 10 cm. What is the size of the cube edge?
  • Poplar
    topole How tall is a poplar by the river, if we know that 1/5 of its total height is a trunk, 1/10th of the height is the root and 35m from the trunk to the top of the poplar?
  • Martha
    stromy_1 Martha likes to walk in the park, the park is square, 7/10 mi on each side. One morning Martha walked around the entire park 3 1/2 times before stopping to rest. How far had she walked?

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