Question 880490
Set up the proportion


(384 messages)/(8 days) = (x messages)/(30 days)


which turns into


384/8 = x/30


-------------------------------------------------------


Now cross multiply and solve for x


384/8 = x/30


384*30 = 8x


11520 = 8x


11520/8 = x


1440 = x


x = 1440



He sent & received <font color="red">1440</font> text messages in 30 days.