Question

A sprinkler placed at the centre of a flower garden sprays water covering a circular area. If the area watered is 1386 cm², find its radius and diameter.

Answer 1

Area of the circle = πr² sq.units 

Area of the circular portion watered = 1386 cm² 

πr² = 1386 

\(\frac{22}{7}\) x r² = 1386

r² = 1386 x \(\frac{7}{22}\)

= 63 x 7 

= 9 x 7 x 7 

r² = 3² x 7² 

r = 3 x 7 

Radius (r) = 21 cm

Diameter (d) = 2r 

= 2 x 21 cm 

Diameter (d) = 42 cm