Nothing in scripture tells us that Mary of Magdalene was a prostitue, and there is no mention of her age.
In Luke 7v36-50 tell of a sinful woman coming to Jesus seeking forgivness, and she is forgiven.
Luke 8 tells us of the women who provided for Jesus, and Mary is named as the first, out of whom Jesus had cast 7 evil spirits.
So, it is assumed that the woman in Luke 7, who is unnamed, and Mary Magdalene are the same person.
Believe what the word of God says.
Why is it that people can believe the latest gossip, but not what the unchanging word of God says?
Ask the people you work with that.
People are so gulliable. They believe whatever is thrown at them, and they catch it without a though.
Maybe that is the problem, they just don't think.
God bless.