could you please show me how to do this

Question

problem? Bob rows 6 miles downstream in 1 hr, joe rows 6 miles upstream in 2 hr. joe rows 1 mile per hour faster.

a. what is each of their speed, bob 6/1=6mph joe 6 + 1 = 7mph is this right??

b. what is the current speed??
downstream R + c = 6/1 6mph
upstream R-C 6/2 = 3mph
6-3/2 = 3/2 or 1 1/2 mph current speed

c. if bob and joe rowing separately , who would complete trip first and by how long.
thank you

Answer 1

a. Vb + Vc = 6.
Vb - Vc = 6/2-1 = 2.
Add the two Eqs:
Eq1: Vb + Vc = 6.
Eq2: Vb - Vc = 2.

2Vb= 8.
Vb = 4 Mi/h = Velocity of Bob's boat.
Joe: Vb = 4 + 1 = 5 Mi/h.

b. In Eq1, substitute 4 for vb:
4 + Vc = 6.
Vc = 6 - 4 = 2 Mi/h = Velocity of the current.

Answer 2

c. Bob: T1 + T2 = 6/6 + 6/2 = 4 hrs.
Joe: 6/7 + 6/3 = 2 6/7 = 2.86 Hrs.

Margin = 4-2.86 = 1.14 hrs.

Answer 3

thank you very much henry , I really appreciate the help. ann