Hello!
The equation 5*18 equals 90. So, there are nine tens in this equation's answer.
Have a wonderful day! :)
-L
Recall your d = rt, distance = rate * time.
b = speed rate of the boat.
c = speed rate of the current.
keeping in mind that, as the boat goes Upstream, against the current, it's speed is not "b", but is really " b - c ", because the current is subtracting speed from it.
likewise, when the boat is going Downstream, because is going with the current, is really going faster at " b + c ".

what is the speed of the boat? well, 61 + c = b.
Answer:
S/2πr-r = h
Step-by-step explanation:
S = 2πr(h + r)
S/2πr = h+r
S/2πr - r = h
Answer: b = r/h
Step-by-step explanation:
To solve for b, simply divide both sides of the equation by h to get:
bh/h = r/h
b = r/h
Hope it helps :) and let me know if you want me to elaborate.