Samira can do a piece of work in 9 days. Sujata can do $\frac{1}{3}$ of the same work in 3 days. If Samira worked alone for 2 days and left, then, in how many days can Sujata alone complete the remaining work ?

7 days

Samira = 9 days, 

Sujata = \(\frac{1}{3}\)W = 3 days = 9 days,

⇒ Samira worked for 2 days alone and left = 1 x 2 = 2 units   ..(Efficiency × Days = Total work)

⇒ Remaining work = 9 - 2 = 7 units,

⇒ Time required by Sujata to complete the remaining work alone = \(\frac{7}{1}\) = 7 days.     ..(\(\frac{Work}{Efficiency}\) = Time)