Fractions + circle - math problems

Number of problems found: 19

Cutting square
From a square with a side of 30 cm, we cut the circle with the highest possible diameter. How many percents of the square content is this circle?
Triangle in circle
Vertices of the triangle ABC lies on a circle with radius 3 so that it is divided into three parts in the ratio 4:4:4. Calculate the circumference of the triangle ABC.
Three shapes
1/5 of a circle is shaded. The ratio of area if square to the sum of area of rectangle and that of the circle is 1:2. 60% of the square is shaded and 1/3 of the rectangle is shaded. What is the ratio of the area of circle to that of the rectangle?
Circumferential angle
Vertices of the triangle ΔABC lies on circle and divided it into arcs in the ratio 2:2:9. Determine the size of the angles of the triangle ΔABC.
Three segments
The circle is divided into 3 segments. Segment A occupies 1/4 of the area, segment B occupies 1/3 of the area. What part is occupied by section C? In what proportion are areas A: B: C?
Semicircle
Calculate the length of a semicircle with a radius of 6cm.
Tree trunk
Calculate the average tree trunk with a circumference of 149 cm.
Coin
How many 50-cent coins must be put in a row that next 50-cent coins after them (above) rolled on it axis?
Circular arc
Calculate the length of the circular arc if the diameter d = 20cm and the angle alpha = 142 °
Irrigation sprinkler
The irrigation sprinkler can twist with an angle of 320° and has a reach of 12 meters. Which area can irrigate?
Hands
The clock shows 12 hours. After how many minutes will angle between the hour and minute hand 90°? Consider the continuous movement of both hands hours.
Ratio of volumes
If the heights of two cylindrical drums are in the ratio 7:8 and their base radii are in the ratio 4:3. What is the ratio of their volumes?
Washer
The washing machine drum washes at 71 RPM. The washing machine motor pulley has a diameter of 8 cm. What must be the diameter of the drum machine pulley when the motor is at 351 RPM?
Mice
Mice consumed a circular hole in a slice of cheese. The cheese has the shape of a circular cut with a radius of 20 cm and an angle of 90 degrees. What percentage of the cheese ate mice if they made 20 holes with a diameter of 2 cm?
A large
A large gear will be used to turn a smaller gear. The large gear will make 75 revolutions per minute. The smaller gear must make 384 revolutions per minute. Find the smallest number of teeth each gear could have. [Hint: Use either GCF or LCM. ]
Cone A2V
The surface of the cone in the plane is a circular arc with central angle of 126° and area 415 cm². Calculate the volume of a cone.
Megapizza
Megapizza will be divided among 100 people. First gets 1%, 2nd 2% of the remainder, 3rd 3% of the remainder, etc. Last 100th 100% of the remainder. Which person got the biggest portion?
Gears
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?
Cone
Circular cone of height 15 cm and volume 5699 cm³ is at one-third of the height (measured from the bottom) cut by a plane parallel to the base. Calculate the radius and circumference of the circular cut.