First find the number of weeks Casey stays: 3 months * 4 weeks/month = <<3*4=12>>12 weeks
Then multiply that number by the weekly rate to find how much she would pay weekly: 12 weeks * $280/week = $<<12*280=3360>>3360
Then multiply the number of months she stays by the monthly rate to find how much she pays monthly: $1000/month * 3 months = $<<1000*3=3000>>3000
Then subtract that number from the total amount she pays if she pays weekly to find her savings: $3360 - $3000 = $<<3360-3000=360>>360
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