Answer:
The elements of the given set are the multiples of 3:
3=3×1
6=3×2
…
363=3×121.
Hence,there exists a bijection between sets A={3,6,9,12,…,363} and B={1,2,3,4,…,121}.
Now,clearly the cardinality of the set B is 121.
Hence,due to bijection between B and A, the cardinality of set A is also 121.
Step-by-step explanation:
