17. A man can row at 8 km/hr in still water. If the river is running at 2 km/hr, it takes him 48
minutes to row to a place and coming back. How
far is the place ?
(a) 1 km
(b) 2 km en
(c) 3 km
(d) 4 km

(c) 3 km

Step-by-step explanation:

Speed in still water: 8 km/h

Speed of river: 2 km/h

Speed downstream: 8 km/h + 2 km/y = 10 km/h

Speed upstream: 8 km/h - 2 km/h = 6 km/h

total time both ways: 48 minutes = 48/60 hour = 0.8 hour

time to go upstream: t

time to go downstream: 0.8 - t

speed = distance/time

s = d/t

d = st

Upstream:

d =  st

d = 6t

Downstream:

d = st

d = 10(0.8 - t)

The distance upstream and downstream is the same.

6t = 10(0.8 - t)

6t = 8 - 10t

16t = 8

t = 0.5

d = 6t = 6(0.5)

d = 3

(c) 3 km

well what did you do it matters what you did : )

step-by-step explanation:

y=-2.5x+12.5

step-by-step explanation:

5y=2x+10

y=0.4x+2

slope=-2.5

5=-2.5*3+b

b=12.5