70. Area A car's rear windshield wiper rotates 125º. The

total length of the wiper mechanism is 25 inches and

the length of the wiper blade is 14 inches. Find the area

wiped by the wiper blade.

175 square inches

Step-by-step explanation:

Area wiped by the wiper blade = Area covered by the whole wiper mechanism - Area that is not being wiped.

Where area of a sector of 125° ... Area = 1/2. r^2. theta ... but with theta in radians

Area covered of the whole wiper mechanism;

= 1/2 * 25^2 * (25pi/36) ... in which (25pi/36) is 125° in radians ...

=217.014pi

Area that is not being wiped;

= 1/2 * (25 - 14) ^2 * (25pi/36)

= 42.014pi

Area wiped by the wiper blade

217.014 - 42.014

Area = 175 square inches