Answer with Explanation:

Work done =5/8

Balance work =(1 -5/8) =3/8

Let the required number of days be x.

Then,5/8 : 3/8 = :: 10 : x   =>   5/8 x x =3/8 x 10

 x =3x 10 x885

 x = 6.

 x =3x 10 x885

 x = 6.