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:
I believe it is A
Step-by-step explanation:
I dont quite remember the formula, but I belive that 30 would be correct because if im remembering correctly the formulas are "a + b = c" and "c - (a/b) = (a/b)
a/b = a or b, depending what they give you
Im wondering the same thing i have this question to
Answer:
<h2>
y = x² - 1</h2>
Step-by-step explanation:
y = -1 for x = 0 {point(0, -1)} means -1 at the end of formula
If we add 1 to y-coordinate of every given point we get the squares of x-coordinate:
(1, 0): 1² - 1 = 0
(2, 3): 2² - 1 = 4 - 1 = 3
(3, 8): 3² - 1 = 9 - 1 = 8
(4, 15): 4² - 1 = 16 - 1 = 15
So for any x:
(x, y) y = x² - 1
