Task: Question Answering
Input (English): Problem: jo ' s collection contains us, indian and british stamps. if the ratio of us to indian stamps is 5 to 2 and the ratio of indian to british stamps is 5 to 1, what is the ratio of us to british stamps ?
Options: a. 10: 5, b. 15: 2, c. 20: 2, d. 25: 2, e. none of these
Output (English): d