At the beginning of the year, Grayson had $45 in savings and saved an additional $19 each week thereafter. Jacob started the year with $90 and saved $16 every week. Let G represent the amount of money Grayson has saved t weeks after the beginning of the year and let J represent the amount of money Jacob has saved t weeks after the beginning of the year. Write an equation for each situation, in terms of t, and determine the who has more money saved after 18 weeks.