Answer:
9.
Step-by-step explanation:
Count the number of digits after the first digit,
This is 9.
7
−
3
1
=
−
3
4
k
k
7
−
31
=
−
34
7kk−31=−34
2
7
−
3
1
=
−
3
4
I think that’s the right answer
They would have 2 because is it 10:1 just double it to be 20:2
Let the boat speed in still water be b.
Let the current speed be c.
The speed going upstream is 20/4 = 5 mph.
The speed going downstream is 32/4 = 8 mph.
b - c = 5 ........(1)
b + c = 8 .......(2)
Adding equations (1) and (2) we get:
2b = 13
b = 13/2 = 6.5
Plugging in the value for b into equation (1) we find c = 1.5.
The boat speed in still water is 6.5 mph and the current speed is 1.5 mph.