Answer:
Yes, it is a proportional relation.
Step-by-step explanation:
Given,
5 text messages a boy sent or received = 7 text messages a girl sent or received,
⇒ 1 text message of a boy = text messages of a girl,
So, x text messages of a boy = text messages of a girl,
Let y represents the text messages of a girl for the x text messages of a boy,
Which is a line,
∵ At (0,0),
( True ),
Thus, line passes through the origin,
Hence,
shows a proportional relation.