A motorboat travels 385 kilometers in 7 hours going upstream and 455 kilometers in 5 hours going downstream. What is the rate of the boat in still water and what is the rate of the current?

Rate of the boat in still water 73 mi/hr

Rate of the current 18 mi/hr

Step-by-step explanation:

Calculation to determine the rate of the boat in still water and the rate of the current

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

Let S represent the speed of the stream

Speed upstream = B-S.

Speed downstream = B+S.

Using the equation for distance

Distance=Rate * Time

Upstream

(B-S)7 = 385

(B+S)5= 455

Simplify first:

B-S=385/7

B-S = 55

B+S=455/5

B+S = 91

Solve by elimination. Add the two equations.

2B=55+91

2B = 146

B=146/2

B = 73 mi/hr

Substitute this into either equation and solve for S.

B+S = 91

73+S = 91

S=91-73

S = 18 mi/hr

Therefore the rate of the boat in still water is 73 mi/hr and the rate of the current is 18 mi/hr

c

step-by-step explanation:

it isn't d, because the interquartile range is from 27-57. and the interquartile range is basically half the data, it's pretty obvious.

it isn't b, because like i said earlier, the interquartile range is from 27-57. 57-27 is 30. the real range has to be longer

not a either. although it looks like it, 3/4 of the data is not greater than 27. but if c is wrong than this should be correct

the correct answer is c, because 13 is the point in which the plot starts

do you mean add both of the equations together

because if you do the answer is 10x-5

step-by-step explanation: