she gets $20 per week allowance.......she babysits 2 hrs a week at 5.50 per hr.....so she gets (2 * 5.50) = $ 11 per week from babysitting...so she is making a total of (20 + 11) = $ 31 per week. But she pays 2.50 a week for school lunch.......so she is basically making (31 - 2.50) = 28.50 per week.
28.50w < = 149.99
w < = 149.99 / 28.50
w < = 5.26 weeks....but if u need it rounded, it would take her approximately 6 weeks....because 5 weeks wouldn't be enough time