Answer: Um i think someone else from your school asked the same exact question and i literally just answered it, just click on my account to see the answer.....
Step-by-step explanation:
For problems such as this, it can be handy to remember that
.. 1/(1/a +1/b) = ab/(a +b)
The time required to do a job is the inverse of the rate at which the job is done. Rates are added when people work together (in math problems, not in real life).
(2:44)*(3:14)/(2:44 +3:14) = 1:28:52.3
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2:44 = 41/15 hours = 82/30 hours
3:14 = 97/30 hours
Using the formula above, we have a "working together" time of
.. (82/30)*(97/30)/(82/30 +97/30) = 82*97/(30*179) = 3977/2685 . . . hours
.. = 1 hour 28 156/179 minutes
.. = 1 hour 28 minutes 52 52/179 seconds
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Learn to use the fraction functions on your calculator. They can be very helpful.
It goes as 1.875. Hope this helped you :)))
4m+9+5m-12=42
9m-3=42
Divide bothsides by 9.
9m/9 -3/9=-0.3=-4
m=-4
