as the power is positive,the focal length is also positive.This implies that the nature of lens is convex.He suffers from hypermetropia as the near point of the eye is greatwer than 25cm.
You just need to keep this in mind;
- When power is -ve,focal length is negative which indicates that the person is suffering from myopia and the nature of lens which is to be used is concave.
- If the power is positive,the focal length is positive,whichy implies that the person suffers frm hypermetropia and he/she has to use a convex lens of suitable positive power.
By the way,the formula of finding focal length frm power is:
D=1f
and f is in meters in the above formula!!