Rita and Mira are ranked 7th and 10th respectively from top in a class of 25. What are their respective ranks from the last.

 19th & 16th

Total number of students = Rank from top + Rank from bottom - 1 

Rita rank from last, 

Total number of students = Rank from top + Rank from bottom - 1 

rank from last = 25 + 1 - 7 = 19

Mira rank from last, 

Total number of students = Rank from top + Rank from bottom - 1 

rank from last = 25 + 1 - 10 = 16

 19th & 16th