The unit rate that the boat can travel during this time frame is 511 kilometers in 1 hour.
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This answer would have to be snakskeewhsof ndxjssoaanshew
X = smaller number, y = larger number
x + y = 15.....x = 15 - y
4x = 2y - 60
4(15 - y) = 2y - 60
60 - 4y = 2y - 60
60 + 60 = 2y + 4y
120 = 6y
120/6 = y
20 = y <==== larger number is 20
x + y = 15
x + 20 = 15
x = 15 - 20
x = - 5
