Question

11.que no.
PLEASE answer quickly

Answer 1

ASSALAMUALAIKUM

let s = speed of boat in still water

then,

(s-4) = speed in upstream and

(S+4) = speed in down stream

Distance in both way is equal

make a distance equation

Distance = time* speed

up distance = down distance

25 (S-4) = 20 (S+4)

25 S-100 = 20 S+80

25 S-20 S = 100+80

5S=180

S=180/5

S=36mph

then,
Distance = time* speed

downstream 25 (36-4) =800

and

upstream d= 25(36-4) =800

both are 800

INSHAALLAH it will help you!