Answer:
S = v1 t1 = 7 t1 traveling downstream
S = v2 t2 = 5 t2 traveling upstream
7 t1 = 5 t2
7 (6 - t2) = 5 t2 since t1 + t2 = 6
42 - 7 t2 = 5 t2
t2 = 42 / 12 = 3.5 hrs so t1 = 2.5 hrs
S = 7 t1 = 7 * 2.5 = 17.5 mi
Also, S = 5 t2 = 5 * 3.5 = 17.5 mi
a. because to divide 6 1/4 and 3 you need to make the improper fraction a mixed number so the equation is 25/4 / 3/1 then you get the recipricol of 3 witch is 1/3 then you multiply 1/3 x 25/4 whitch is 25/12=2 1/12
Here is the equation to find that answer A=bh+2ls+ib i got it off line if its not right im sory
