No, 45/100 is greater. 3/8 as a decimal is .
0.375 and 45/100 is 0.45 the tenth place is larger making the number larger
When you write an equation in the slope-intercept form

the two coefficients m and b represent, respectively, the slope and the intercept.
So, in your case, m=1/4 and b= -7, which leads to the equation

4t + 75 => 475, t = 100
Is this what you were looking for?