10.Two persons could fit new windows in a house in 3 days.
(i) One of the people fell ill before the work started. How long would the job take now?

(ii) How many persons would be needed to fit the windows in one day?


Answer :

We can see that on increasing the number of persons, less time will be required to complete a job.Thus, the quantities are in inverse proportion.


(i) Let the required number of days be x.

∴\(x_1y_1 = x_2y_2\)

\(\Rightarrow 2 \times 3 = 1 \times x\)

\(\Rightarrow x = 6\)

Hence, the required number of days = 6 days

(ii) Let the required number of persons be y.

∴\(x_1y_1 = x_2y_2\)

\(\Rightarrow 2 \times 3 = y \times 1\)

\(\Rightarrow y = 6\)

Hence, the required number of persons = 6.

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