Task: Question Answering
Input (English): Problem: two trains, one from howrah to patna and the other from patna to howrah, start simultaneously. after they meet, the trains reach their destinations after 25 hours and 81 hours respectively. the ratio of their speeds is :
Options: a. 2: 3, b. 4: 3, c. 9: 5, d. 9: 16, e. none of these
Output (English): c