Answer: the speed of the current is 9 mph.
Step-by-step explanation:
Let x represent the speed of the current.
A boat can travel 21 mph in still water. If it travels 270 miles with the current. It means that the total speed with which the boat travelled with the current is (21 + x) mph.
Time = distance/speed
Time spent by the boat in travelling 270 miles is
270/(21 + x)
In the same length of time, it travels 108 miles against the current. It means that the total speed with which the boat travelled against the current is (21 - x) mph.
Time = distance/speed
Time spent by the boat in travelling 108 miles is
108/(21 - x)
Since the time is the same, then
270/(21 + x) = 108/(21 - x)
270(21 - x) = 108(21 + x)
5670 - 270x = 2268 - 108x
108x + 270x = 5670 - 2268
378x = 3402
x = 3402/378
x = 9
K.E=0.5mv^2
GPE=mgh
The child has both K.E and GPE
g is taken as 9.81
<h3><u>Answer</u>:- </h3>
<h3><u>Solution:-</u></h3>
<u>Given </u><u>that </u><u>:</u><u>-</u>
- job last for h hours
- Cost of job lasting more than 1 hour = $30
- Cost for the first hour = $75
Remaining hours for which the job will last after first hour= (h-1)
<u>Therefore</u>,
Cost for subsequent hours = 30×(h-1)
= 30(h-1)
Total Cost for job = Cost for 1st hour + Cost for subsequent hours
Answer:
80, 40, 40
Step-by-step explanation:
The rule is if the number before the tens place is 5 or more round up and if it is 4 or less round down.
I like to look at it without the rule and what makes sense.
82.14: my choices are 80 or 90. What number is 82.14 closer to on the number line? 80.
38.5 The choices are 30 and 40. This number on a number line would be closer to 40
41.3 The choices are 40 and 50. On a number line this number would be closer to 40.
