1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
valentina_108 [34]
3 years ago
8

A boat can travel 21mph in still water. If it travels 270 miles with the current in the same length of time it travels 108 miles

against the current, what is the speed of the current?
Mathematics
1 answer:
erica [24]3 years ago
7 0

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

You might be interested in
Write the equation of the line in fully simplified slope-intercept form.​
Nadya [2.5K]
The answer is y=-2/3x+3 :)
8 0
3 years ago
An 18-foot ladder is leaning against a vertical brick wall. The base of the ladder is 9 feet away from the wall.
Triss [41]
A^2 + b^2 = c^2
a^2 + 9^2 = 18^2
a^2 + 81 = 324
a^2 = 243
a = 15.589 = 15.6 feet is the angle the ladder is at :)
8 0
3 years ago
Help me this is very hard
bezimeni [28]
You can use this phrase to help you...
•King
•Henry
•Drinks
•Many cups of
•Chocolate
•Milk
Which also stands for the metric units...
•Kilometer
•Hectometer
•Decameters
•Meter
•Centimeter
•Millimeter
And whenever you need to convert from 1 unit to the next, just jump back and forth on the system



7 0
3 years ago
What is the angle of rotation to bring the object or figure back to its original position and opposite position?​
zavuch27 [327]

Answer:

Original: 360 degrees

Opposite: 180 degrees

Step-by-step explanation:

I have no idea where 360 degrees for the full rotation. But that wasn't necessary.

How to calculate Opposite:

360/2=180

6 0
3 years ago
Read 2 more answers
Consider z = 3StartRoot 3 EndRoot + 3i. What happens to the modulus and argument when z is raised to the 4th power?
exis [7]

Answer:

It's A

Step-by-step explanation:

Just took it and it matches

6 0
3 years ago
Other questions:
  • Which equation describes this line?
    11·2 answers
  • Help...
    12·1 answer
  • Using the ratio of perfect squares method, what is the square root of 96 rounded to the nearest hundredth?
    5·1 answer
  • The weight of and object on the moon, m, is about 1/6 of the object's weight on earth, e. Which equation represent the approxima
    7·1 answer
  • Can someone explain how to do #3?
    5·2 answers
  • What is the slope of a line parallel to the line with equation 5x + 3y = 7?
    13·1 answer
  • Can someone please help me, everyone is taking my points :(
    12·1 answer
  • Write a story that could represent this math problem. A rectangle partitioned into thirds five times. The first part, the second
    12·1 answer
  • Simplify (Remember to simplify means to write an equivalent expression that uses each variable on')
    5·1 answer
  • Levi rented a movie for $3.20 and bought a package of candy for $2.55. How much money did Levi spend in total?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!