Total age of Rashmi and Surbhi (5 yr ago) 20 x 2 = 40 yr.
Total age of Rashmi and Surbhi (at present) = 40 + 5 + 5 = 50 yr.
Total age of Rashmi, Surbhi and Meeta (at present) = 30 x 3 = 90 yr.
∴ Present age of Meeta = 90 - 50 = 40 yr.
∴ Age of meeta after 15yr. = 40 + 15 = 55 yr.