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:
The rock splashes down when h(t) = 0. Set h(t) = 0 and solve for t using quadratic formula.
0 = − 4.9t^2 + 178t + 325
t = 38.07, -1.74
(Throw away the negative answer, since time can't be negative.)
t = 38.07 sec
Please Mark Brainliest If This Helped!
Answer:
you would need to make sure that the line does not touch the 1 mark, but near it. On a digital graph(TI84) you would press 2nd graph
Step-by-step explanation:
Did it
Answer:
D
Step-by-step explanation:
Given the quadratic
d = - 16t² + 12t ← subtract d from both sides
- 16t² + 12t - d = 0 ← in standard form
with a = - 16, b = 12, c = - d
Use the quadratic formula to solve for t
t = ( - 12 ±
) / - 32
= ( - 12 ±
) / - 32
= ( - 12 ±
) / - 32
= ( - 12 ± 4
) / - 32
=
± 

=
± 

=
±
→ D
Answer:
1/15
Step-by-step explanation:
This is probably too late but I'll do it anyway.
There are 10 cards in all.
of the 10, 3 are green.
So your chance of drawing the first green is 3/10
Now you have 9 cards in total left.
Two of them are green
Your chance of drawing a green card again is 2/9
Your total chance of drawing 2 green cards is
2/9 * 3/10 = 6/90
2/9 * 3/10 = 1/15