A number x is chosen at random from the numbers -3, -2,-1, 0, 1, 2, 3 the probability that |x| < 2 is:
(a) 5⁄7
(b) 2⁄7
(c) 3⁄7
(d) 1⁄7
[Note: option (c) is correct]
Answers
ANSWER: you are wrong 5/7 is the answer
Explanation:
bit (a)
Answer:
(c) 3⁄7
Step-by-step explanation:
Probability of an event:
If the Probability of occurrence of an event E is P(E):
- number favorable outcomes meaning the total number of values of x, satisfying the given conditions.
- total number outcomes, ofcourse, means the total number of values of x given to us.
Here's, the condition imposed on x is:
|x| < 2
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Absolute Value:
(|.|) means absolute value!
that is the value of -x and +x, as long as x is same for both, i.e., x.
For example:
we have two numbers +5 and -5
|+5| = 5,
|-5| = 5
Here's it! (|.|) of both values gave the same result, I.e., it's magnitude.
Properties of absolute value function:
- It's always positive, I.e., starts from 0 and tends to infinity.
- It's equal to the set of whole numbers, I.e.,
|x| ∈ { 0, 1, 2,. .∞ }
- Absolute value function yields two values! I.e.,
|x| = +x, -x
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Back to the question:
So,
|x| < 2
==> |x| ∈ {0, 1}
[Note: 2 isn't included! That's because there's not an equal to sign wth "<". We'll not include the limit when "<" is used]
(Now, |x| = +x, and -x)
•°• |1| = +1, and -1
|0| = 0
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Probability of the given event:
That gives us 3 values of x that satisfy the condition
==> number favorable outcomes = 3
Total number of values of x = 7
==> total number outcomes = 7
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Answer:
_____________
Hope this helps! :)