Trig question- how do i find T in this equation

First, subtract 5 from both sides of the equation to get

1.7 = 2.5 sin(30t)      Now divide both sides by 2.5

.68 = sin(30t)       now use the arcsin fxn to get

42.84 = 30t          Now divide both sides by 30

1.428 = t

Your next post gives more information  .....  t is in hours    1.428 hours     1 hour 25 minutes 40.8 seconds