One blade cleans a sector of radius 28 cm and angle 120°: (120/360) x (22/7) x 28² = 2464/3 cm². With two blades, total cleaned area is 2 x (2464/3) = 4928/3 = 1642.67 cm².
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Minor sector is (60/360) x 3.14 x 15² = 117.75 cm². Equilateral triangle area is (√3/4) x 15² = 97.31 cm². Minor segment is 117.75 – 97.31 = 20.44 cm². Major segment is 706.5 – 20.44 = 686.06 cm².
Radius is 10 cm. (i) Minor sector area is (90/360) x 3.14 x 10² = (1/4) x 314 = 78.5 cm². (ii) Major sector area is (270/360) x 3.14 x 10² = (3/4) x 314 = 235.5 cm².
In 60 minutes, the minute hand turns 360°, so in 10 minutes it turns (360/60) x 10 = 60°. The area swept is a sector: (60/360) x (22/7) x 7² = 77/3 = 25.67 cm².
Circumference 2 x (22/7) x r = 44 yields radius r = 7 cm. A quadrant has angle 90°, so its area is (1/4) x π x r² = (1/4) x (22/7) x 7² = 77/2 = 38.5 cm².