Need helpp fastt plss will give brainliest to who is correct plss helpp

Answer:
6
Step-by-step explanation:
List all the factors for 15 ( 1and 15) (3 and 5) use a number thats is bigger than Leila's but not bigger than Jo's the only one is 3, multiply 2 and 3, and 3 and 3 your numbers should be 6 (2x3) and 9 (3x3) add them together to make 15 then you got it.