First find the total cost of the drink tickets: 5 tickets * $7/ticket = $<<5*7=35>>35
Then add that cost to the cost of the ticket to find the total cost: $35 + $181 = $<<35+181=216>>216
Then multiply Jenna's hourly rate by the number of hours she works each week to find her weekly earnings: $18/hour * 30 hours/week = $<<18*30=540>>540/week
Then multiply her weekly earnings by the number of weeks she works each month: $540/week * 4 weeks/month = $<<540*4=2160>>2160/month
Then divide the cost of the concert by Jenna's monthly earnings and multiply by 100% to express the answer as a percentage: $216 / $2160 * 100% = 10%
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