Which of the following quantities vary directly with each other?

(i) Number of articles (x) and their price (y)


(ii) Weight of articles (x) and their cost (y).


(iii) Distance x and time y, speed remaining the same.


(iv) Wages (y) and number of hours (x) of work.


(v) Speed (x) and time (y) distance covered remaining the same).


(vi) Area of a land (x) and its cost (y).

(i) If number of articles is increasing then cost will also increase. So it is a case of direst proportion


(ii) Cost will also increase when weight of the article is increasing. So it is a case of direst proportion


(iii) Time will increase when distance will increase, if speed remaining constant. So it is a case of direst proportion


(iv) Wages will increase if the number of working hours is increasing. So it is a case of direst proportion


(v) For same distance time taken will reduce if speed is increased. So it is not a case of direst proportion


(vi) Cost for the land will increase if its area will increase. So it is a case of direst proportion


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