Swaroopi read \({2 \over 5}\) of a book on the first day and another \( {4 \over 15}\) of the book on the second day. what share of the book has swaroopi read during the first two days ?
1
\( {8 \over 15}\)
2
\( {2 \over 3}\)
3
\( {7 \over 15}\)
4
\( {11 \over 15}\)