Answer:
Working together, they will finish the job in 1 hour, 25 minutes, and 42.6 seconds.
Step-by-step explanation:
Given that Ted can change an advertisement on a billboard in 5 hours, while Marie can do the same job in 2 hours, to determine how long it would take them if they worked together the following calculation must be performed:
Ted 1/5 in 1 hour
Marie 1/2 in 1 hour
1/5 + 1/2 = X
5X + 2X = 10
7X = 10
X = 10/7
X = 1 3/7
60/7 x 3 = 25.71
60 x 0.71 = 42.6
So, working together, they will finish the job in 1 hour, 25 minutes, and 42.6 seconds.
The probability that he is in the right job is 0.65, so the probability he is in the wrong job is 0.35, and similarly, the probability that the test is inaccurate is 0.3. Thus, the probability that someone is in the right job and the test is then wrong is 0.65*0.3=.195, and the probability that someone is in the wrong job and the test is wrong is 0.35*.3=.105.
It would be easier to translate this into mathematical terms first.
Let n = the unknown number
6n <span>> n + 20
Subtracting both sides by n to simplify:
6n - n </span><span>> n + 20 - n
</span>5n <span>> 20
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Dividing both sides by 5:
5n/5 </span><span>> 20/5
</span>n <span>> 4
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Among the choices, the correct one is the second choice.
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