1. cannot be formed
2. can be formed in exactly two ways
3. can be formed in exactly one way
4. none of these
can be formed in exactly one way
1. She can have 4 ages
2. She can have 2 ages
3. given that all primes are distinct she can have only one age
4. a and c
5. b and c
b and c
1. 5/7
2. 3/7
3. 3/5
4. 1/3
3/7
1. 1/63
2. 2/35
3. 2/63
4. 9/14
2/63
1. 6/13
2. 5/26
3. 5/13
4. 7/26
5/26
1. 1/216
2. 1/36
3. 4/216
4. 3/216
1/216
1. 18/145
2. 18/29
3. 36/135
4. 36/145
36/145
1. 9/30
2. 8/30
3. 10/30
4. 11/30
10/30
1. 5/21
2. 9/42
3. 11/42
4. 4/21
9/42
1. 1/5
2. 5/6
3. 4/5
4. None of these
1/5