sir i got pq / ac = 3/7 now triangle pca ~ triangle dqp so ap / pd = ac / qp so ap /pd = 7:3 and then was confused as i had used hardly any info…. Reply
Sir even i think that only one similarity is enough to solve this one. 🙂 Just the way Girish said. Am I right ? Reply
CAT-holics 
sir i got
pq / ac = 3/7
now triangle pca ~ triangle dqp
so ap / pd = ac / qp
so ap /pd = 7:3
and then was confused as i had used hardly any info….
Sir even i think that only one similarity is enough to solve this one. 🙂 Just the way Girish said. Am I right ?