During one part of its migration, a salmon is swimming upstream at 6 mph. The current is flowing downstream at 3 mph at an angle of 7°. How fast is the salmon moving upstream?

Question

radar · Answer

Doesn't the problem state that Mr. Salmon is swimming upstream at 6 mph?

anonymous · Answer

do I just subtract then?

radar · Answer

I guess they want you to solve the rate he is moving with respect to land.  So you would subtract, but not the total 3 mph since it is at  an angle of 7 degrees rather than 0 degree (in direct opposition.  I am guessing that you use cosine 7 degrees as a factor multiplying the three mph and subtracting the results.  Just a SWAG!

anonymous · Answer

ok worth a try thank you!