# Circle - 6th grade (11y) - math problems

#### Number of problems found: 75

• Tractor wheels 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?
• On a 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?
• Length of the arc What is the length of the arc of a circle k (S, r=68mm), which belongs to a central angle of 78°?
• Winch drum 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
• Tunnel boring How much material did they dig when cutting the 400m long tunnel? The content of the circular segment, which is the cross section of the tunnel is 62m2. Find the radius of the circle with area S = 200 cm².
• Coal mine The towing wheel has a diameter of 1.7 meters. How many meters does the elevator cage lower when the wheel turns 32 times? Calculate the radius of the circle whose length is 107 cm larger than its diameter
• Steel tube The steel tube has an inner diameter of 4 cm and an outer diameter of 4.8 cm. The density of the steel is 7800 kg/m3. Calculate its length if it weighs 15 kg.
• Lake or pond The landlord has a square lake. Trees grow around this lake. The lake wants to enlarge the pond twice and not cut down or flood any tree. How will he do that?
• Curved surface area CSA A cylinder 5cm high has a base radius(7/2) cm. Calculate the curved surface area.
• Volume of cone Find the volume of a right circular cone-shaped building with a height of 9 m and a radius base of 7 m.
• Clock hands The second hand has a length of 1.5 cm. How long does the endpoint of this hand travel in one day?
• Bike wheel The bike wheel has a radius of 30cm. How many times does it turn if we go on a 471m bike?
• Rhombus EFGH Construct the rhombus EFGH where e = 6.7cm, height to side h: vh = 5cm
• Calculate Calculate the area of a circle whose radius is 5 dm.
• Annulus The radius of the larger circle is 8cm, the radius of smaller is 5cm. Calculate the contents of the annulus.
• Perimeter to area Calculate the area of a circle with a perimeter of 15 meters.
• Diameter to area Find the area of a circle whose diameter is 26cm.
• 2d shape Calculate the content of a shape in which an arbitrary point is not more than 3 cm from the segment AB. The length of the segment AB is 5 cm.

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