Math
posted by Tracy .
Stephanie received twentyone email messages. Three of them were from her mother. What fraction of the messages were not from her mother?
Can you please provide the answer in numeric form?

Use the same strategy as the dress problem.
Messages from her mother = 3
Messages in all = 21
Messages NOT from her mother = 213=18
So fraction of messages NOT from her mother = 18/21 = 6/7