(ii) to calculate central angle:
We must know total votes =90+120+150
=360
By treating 360∘ as an angle, all three seasons combining together, it represents a complete one revolution.
Since, number of votes for summer season =90 votes
⇒ central angle of Summer season sector is
=90360×360∘
=90∘
Similar way for other two seasons,
Votes for Rainy season is =120 votes
⇒ Central angle =120360×360∘
=120∘
Votes for Winter season =150 votes
⇒ Central angle =160360×360∘
=150∘
(iii)