Without stopping to rest they will arrive in 300/50= <<300/50=6>>6 hours.
They need to stop to rest after every 2 hours except for the last 2 hour stretch of time, which is when they reach New York, so they rest (6/2)-1= 3-1 = <<6/2-1=2>>2 times.
The time they spend resting is 2*30= <<2*30=60>>60 minutes or 1 hour.
So they will arrive in 6+1= <<6+1=7>>7 hours.
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