Jill's second customer buys 4 times more than her first customer's 5 boxes, so they buy 4*5=<<4*5=20>>20 boxes
Jill's third customer buys half of what her second customer bought, so that means they buy 20/2= <<20/2=10>>10 boxes
Jill's fourth customer buys 3 times as many as what her third customer bought, so that means they buy 10*3= <<3*10=30>>30 boxes
Adding in the 5 boxes sold to the first customer, and the 10 boxes sold to the last one, that means Jill has sold 5+10+20+10+30= <<5+10+20+10+30=75>>75 boxes
Since Jill's goal is 150 boxes sold, and she's only sold 75 so far, she needs to sell 150-75=<<150-75=75>>75 more boxes to hit her goal
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