A boat travels between two cities that are 18 miles apart. When going downstream, with the current, the trip takes 9/8 hour(s). Returning upstream, against the current, the boat covers the same distance in 9/5 hour(s). What is the current of the river? miles per hour What is the speed of the boat in still water?

the speed of the boat in still water is 13 mph.

the current of the river is 3 mph

Step-by-step explanation:

Let x represent the speed of the boat in still water.

Let y represent the current of the river.

The boat travels between two cities that are 18 miles apart.

When going downstream, with the current, the trip takes 9/8 hour(s). The total speed of the boat would be (x + y) mph

Distance = speed × time

Distance travelled while going downstream is

18 = 9/8(x + y)

18 = 1.125(x + y)

Dividing both sides by 1.125, it becomes

16 = x + y - - - - - - - - - - 1

Returning upstream, against the current, the boat covers the same distance in 9/5 hour(s). The total speed of the boat would be (x - y) mph. Distance travelled while going upstream is

18 = 9/5(x - y)

18 = 1.8(x - y)

Dividing both sides by 1.8, it becomes

10 = x - y - - - - - - - - - - 2

Adding equation 1 to equation 2, it becomes

26 = 2x

x = 26/2 = 13

Substituting x = 13 into equation 2, it becomes

10 = 13 - y

y = 13 - 10

y = 3

2/5

step-by-step explanation:

$20.01

step-by-step explanation:

the sale price is (1.00 - 0.77)($87), or 0.23($87), or $20.01.