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.
Answer:
<h2>
503 cm²</h2>
Step-by-step explanation:
The surface area of the figure is sum of areas of two triangles and three ractangles:

Answer:
vertical angle theorem
Step-by-step explanation:
angles that are opposite of each other and formed by two intersecting straight lines, are congruent.
The formula for the circumference of a circle is pi * r * 2
First we solve for r (the radius)
pi*r*2 = C
pi*r*2 = 18
Divide 18 by 2
pi*r = 9
Then divide 9 by 3.14
pi= 9/3.14 which is 2.866
The diameter is 2 times length of the radius so multiply 2.866 by 2
The diameter is about 5.732
(And you can round of course)
Hope that helped