SOLUTION: A ship made a trip of 126 mi in 12 h. The ship traveled the first 48 mi at a constant rate before increasing its speed by 5 mph. It traveled another 78 mi at the increased speed. F
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Question 1073934: A ship made a trip of 126 mi in 12 h. The ship traveled the first 48 mi at a constant rate before increasing its speed by 5 mph. It traveled another 78 mi at the increased speed. Find the rate of the ship for the first 48 mi.
......... mph Answer by jorel1380(3719) (Show Source):
You can put this solution on YOUR website! Let n be the initial speed of the ship. Then the increased speed would be n+5. So:
48/n + 78/n+5=12
48(n+5)+78n=12(nē+5n)
126n+240=12nē+60n
12nē-66n-240=0
2nē-11n-40=0
(2n+5)(n-8)=0
n=-5/2 or 8
Throwing out the negative value, we get the initial rate of the ship to be 8 mph. ☺☺☺☺
