There are 3 families of 4 meaning there are 3*4 =<<3*4=12>>12 people in the vacation rental
They all use 1 oversized beach towel a day so they use 1*12 = <<1*12=12>>12 towels a day
They use 12 towels a day for 7 days so in one week they use 12*7 = <<12*7=84>>84 beach towels
The washing machine can only hold 14 towels and they have 84 towels to wash which means there are 84/14 =<<84/14=6>>6 loads of laundry
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