Chloe and Allison were comparing text messages during lunch. Allison sent 18 text messages today. Allison sent one-third of the amount of text messages sent by Chloe. Write an equation to determine how many text messages Chloe sent.
A$t+3=18$
B$\frac{t}{3}=18$
C$t-3=18$
D$3t=18$
A$t+3=18$
B$\frac{t}{3}=18$
C$t-3=18$
D$3t=18$