What is 2-b/3=-5/2

Please explain thoroughly and only explain the 2-step version

Gigi earned $65 for 5 hours of gardening. she earned $90 for 9 hours of office work. which statement correctly compares gigi’s earning per hour for gardening and office work? she earned $3 more per hour for office work than for gardening. she earned $4 more per hour for office work than for gardening. she earned $3 more per hour for gardening than for office work. she earned $4 more per hour for gardening than for office work.